Duplicated definition or Non-normalized message of error code

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

cd $working_dir/tidb && tools/check/check-errdoc.sh

2. What did you expect to see? (Required)

Generate successfully

3. What did you see instead (Required)

Generate successfully, output:
Duplicated error code: ddl:8200
Duplicated error code: ddl:8200
Duplicated error code: ddl:8200
Duplicated error code: ddl:8200
Non-normalized error: scan break error
Duplicated error code: types:1292
Non-normalized error: can not add because sorted
Duplicated error code: ddl:1273
Non-normalized error: insert statement not found
Non-normalized error: proto: negative length found during unmarshaling
Non-normalized error: proto: integer overflow
Non-normalized error: proto: unexpected end of group
Non-normalized error: label constraint should be in format '{+|-}key=value'
Non-normalized error: unsupported label constraint
Non-normalized error: conflicting label constraints
Non-normalized error: label constraints in map syntax have invalid replicas
Non-normalized error: invalid label constraints format
Non-normalized error: label constraints with invalid REPLICAS
Non-normalized error: invalid bundle ID
Non-normalized error: invalid bundle ID format
Non-normalized error: REPLICAS must be 1 if ROLE=leader
Non-normalized error: the ROLE field is not specified
Non-normalized error: no rule of such role to drop
Duplicated error code: planner:8108
Non-normalized error: retryable: lock not found
Non-normalized error: retryable: already rollback
Non-normalized error: retryable: replaced by another transaction
Duplicated error code: planner:1046
Non-normalized error: Pattern not match
Non-normalized error: invalid syntax

4. What is your TiDB version? (Required)

master