[okhttp-gson] Make initializer block for GSON builder static #16860

[blutorange]

Make initializer block for GSON builder static, see #16860

• Fixes [BUG][JAVA] Static Initializer Block missing in JSON support class #16860
• I tested the changes locally with an openapi file from our project and it works as expected. The static is called and e.g. JSON.deserialize can be used without having to call new JSON()

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[wing328]

thanks for the fix, which has been merged.

sorry for taking a bit long to review as there're too many PRs