Add JavaClientCodegen RxJava option tests

[amirdeljouyi]

test: add JavaClientCodegen processOpts coverage

Hi,

I added a couple of focused processOpts() checks for JavaClientCodegen. They cover RxJava option normalization, including the case where RxJava 2 and 3 are both configured, and the explicit supportUrlQuery conversion for the Apache client.

The main covered areas are the RxJava handling at JavaClientCodegen.java:425-428 and the supportUrlQuery conversion at JavaClientCodegen.java:512-518. Branch coverage for JavaClientCodegen increases by about 2%.

I hope you find these tests useful. 😄 Please let me know if you have any questions or concerns.

Thanks,
Amir

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Summary by cubic

Add unit tests for JavaClientCodegen.processOpts to validate RxJava option handling and supportUrlQuery conversion for the Apache client. Tests cover the case where both RxJava2 and RxJava3 are set (RxJava3 wins) and ensure supportUrlQuery string values convert to booleans; branch coverage increases ~2%.

^{Written for commit 83cc8ca. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[wing328]

thanks for the PR

shall we simply remove/deprecate the RxJava2 option ?