Specify Gradle version for linux workflow to ensure compatibility with JDK 11

[Mattias-Sehlstedt]

The current linux workflow does not work for two reasons:

• The -b flag used has been deprecated and removed
• The Gradle version used is by default 9.0, this is not compatible with JDK 11

I have adjusted for these errors by changing the flag and setting the Gradle version to the lastest supporting JDK 11.

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• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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[wing328]

thanks for the PR which has been merged

have a nice weekend

[wing328]

@Mattias-Sehlstedt looks like linux workflow is completely skipped as line 72 has issues: https://github.com/OpenAPITools/openapi-generator/actions/runs/16955828402

can you please take a look when you've time?

[wing328]

no worry. fixed via #21743

[Mattias-Sehlstedt]

Thanks for the fix 👍