[Java] Add useTags config option support for java client code generation (#10109)

Created by: jekkel

Feature request: https://github.com/OpenAPITools/openapi-generator/issues/10109

This PR adds a new configuration option "useTags" to the Java generator similar to the one that can be found e. g. in the Spring generator. The flag defaults to true to keep backwards compatibility (despite the default for the other generators is false). Setting it the false will prevent the generator to create one interface per tag (which might be not desirable).

There has been a similar PR before, but it has been closed without comment: https://github.com/OpenAPITools/openapi-generator/pull/10156

/cc Technical committee members @bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608

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