THRIFT-5940: Make generated Ruby code RuboCop compliant

[kpumuk]

This change addresses Rubocop offenses in the generated code, mostly spacing:

• extra blank lines around top-level generated blocks
• message=nil instead of message = nil
• trailing whitespace in generated service inheritance lines
• enum constant rendering with incorrect indentation
• blank RDoc lines emitted as # (trailing whitespace) instead of #

Additionally, we generate all Thrift files for Ruby so that SCA job actually ensures they are compliant.

• Did you create an Apache Jira ticket? THRIFT-5940
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• Did you squash your changes to a single commit? (not required, but preferred)
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• If your change does not involve any code, include [skip ci] anywhere in the commit message to free up build resources.