[Java][WebClient] Propagate OpenAPI Deprecations to Generated ApiClient-methods

[Chrimle]

Closes #22675. Reported by, and solution suggested by @parkito. Propagates deprecated-property set on endpoints in OpenAPI Specs, to apply to the corresponding generated methods in ApiClient. This will annotate the method(s) with @Deprecated, as well as add the JavaDoc-tag @deprecated (with an empty description).

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Summary by cubic

Propagates the OpenAPI deprecated flag to generated Java WebClient ApiClient WithHttpInfo methods. This adds @deprecated and a Javadoc @deprecated note so IDEs warn on deprecated endpoints.

• New Features
  • Emit @deprecated and Javadoc @deprecated for operationIdWithHttpInfo when the OpenAPI operation is deprecated.
  • Regenerated petstore WebClient samples to reflect the new annotations.

^{Written for commit 78ce2be. Summary will update on new commits.}

[Chrimle]

Probably want to apply this functionality/behavior to the other flavors of java-generators. However, probably cleaner to do them separately, no?

[cubic-dev-ai]

No issues found across 5 files

[Chrimle]

Ready for review @wing328 🙌

[wing328]

lgtm. thanks for the PR