Better handling of Inline schema

[wing328]

Skip allOf inline subschema created as $ref

To fallback, please use the --inline-schema-name-defaults option as follows

e.g. --inline-schema-name-defaults REFACTOR_ALLOF_INLINE_SCHEMAS=true

(csharp client generators has this fallback enabled by default)

cc @OpenAPITools/generator-core-team

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• Read the contribution guidelines.
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  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
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