Add option to skip reusing inline schemas

Add option to skip reusing inline schemas by providing SKIP_SCHEMA_REUSE=true to inline scheme naming default option, e.g. --inline-schema-name-defaults SKIP_SCHEMA_REUSE=true

This allow users to map each schemas that are previously automatically mapped to the same inline schema due to identical definition.

Added tests and updated doc.

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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh

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cc @OpenAPITools/generator-core-team