Add github metadata field to all examples

Many cross-service examples are missing the github field, which specifies the path to the folder that contains the README for the example. The result is that examples that do not have this field are omitted from the README generated by WRITEME. This epic tracks the work to update this field. Once all examples have the field, we will update the validator to make it required in the future.

Current output from the updated validator:

ExampleErrors with 46 errors:
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FSA, example cross_FSA Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FSA, example cross_FSA Ruby:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FSA, example cross_FSA JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_PAM, example cross_PAM Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_PAM, example cross_PAM Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_PAM, example cross_PAM JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_PAM, example cross_PAM Rust:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RedshiftDataTracker, example cross_RedshiftDataTracker Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RedshiftDataTracker, example cross_RedshiftDataTracker Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SQSMessageApp, example cross_SQSMessageApp Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SQSMessageApp, example cross_SQSMessageApp Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RDSDataTracker, example cross_RDSDataTracker Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RDSDataTracker, example cross_RDSDataTracker Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RDSDataTracker, example cross_RDSDataTracker PHP:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RDSDataTracker, example cross_RDSDataTracker JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SnsPublishSubscription, example cross_SnsPublishSubscription Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SnsPublishSubscription, example cross_SnsPublishSubscription Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LexChatbotLanguages, example cross_LexChatbotLanguages Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LexChatbotLanguages, example cross_LexChatbotLanguages JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_DynamoDBDataTracker, example cross_DynamoDBDataTracker Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_DynamoDBDataTracker, example cross_DynamoDBDataTracker Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_TextractExplorer, example cross_TextractExplorer JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SubmitDataApp, example cross_SubmitDataApp Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SubmitDataApp, example cross_SubmitDataApp Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_SubmitDataApp, example cross_SubmitDataApp JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaAPIGateway, example cross_LambdaAPIGateway Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaAPIGateway, example cross_LambdaAPIGateway JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaScheduledEvents, example cross_LambdaScheduledEvents Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaScheduledEvents, example cross_LambdaScheduledEvents JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_ServerlessWorkflows, example cross_ServerlessWorkflows Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_TranscriptionStreamingApp, example cross_TranscriptionStreamingApp JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RekognitionPhotoAnalyzerPPE, example cross_RekognitionPhotoAnalyzerPPE Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RekognitionPhotoAnalyzer, example cross_RekognitionPhotoAnalyzer Kotlin:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RekognitionPhotoAnalyzer, example cross_RekognitionPhotoAnalyzer Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RekognitionPhotoAnalyzer, example cross_RekognitionPhotoAnalyzer JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_RekognitionVideoDetection, example cross_RekognitionVideoDetection Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_DetectFaces, example cross_DetectFaces Rust:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_DetectLabels, example cross_DetectLabels Rust:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_Telephone, example cross_Telephone Rust:1 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaForBrowser, example cross_LambdaForBrowser JavaScript:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_LambdaForBrowser, example cross_LambdaForBrowser JavaScript:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FMPlayground, example cross_FMPlayground .NET:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FMPlayground, example cross_FMPlayground Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_FMPlayground, example cross_FMPlayground Python:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_ServerlessPromptChaining, example cross_ServerlessPromptChaining Python:3 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
	In C:\Users\larencra\repos\aws-doc-sdk-examples\.doc_gen\metadata\cross_metadata.yaml at cross_MonitorDynamoDB, example cross_MonitorDynamoDB Java:2 has a missing or empty github field. This field should contain the path to the folder that contains the README that describes the example.
46 errors found, please fix them.