Deprecation warning from Serverless Variables Resolver when deploying to GCP using serverless template

Describe the bug

Serverless: Deprecation warning: Variables resolver reports following resolution errors:
              - Cannot resolve variable at "provider.environment.CUBEJS_APP": Value not found at "self" source,
              - Cannot resolve variable at "functions.cubejsProcess.events.0.event.resource": Value not found at "self" source
            From a next major this will be communicated with a thrown error.
            Set "variablesResolutionMode: 20210326" in your service config, to adapt to new behavior now
            More Info: https://www.serverless.com/framework/docs/deprecations/#NEW_VARIABLES_RESOLVER

To Reproduce Steps to reproduce the behavior:

1. npm install -g serverless
2. npx cubejs-cli create -d bigquery -t serverless-google
3. serverless deploy -v
4. See warnings

Expected behavior Should use self variable fine

Version: 0.27