[java][okhttp-gson] Keep AST small when using builder

[janisz]

Currently when we use gson builder all calls are connected with dot.
This results in pretty long instruction that is problematic to parse for AST tools (e.g. lombok).
To fix this we can slice this giant call into series of direct calls on named builder.
As a result we get multiple short and easy to parse instructions instead of one long.

Fixes:

• [BUG] 6.0.0 causes lombok crash #12595

Refs:

• Bump openapi-generator-maven-plugin from 5.4.0 to 6.0.0 in /stackrox-container-image-scanner stackrox/jenkins-plugin#158
• Catch StackOverflowError on drill and add node info projectlombok/lombok#3213
• StackOverflowError using Javac with DbSetup DataSet projectlombok/lombok#1118
• [Java][okhttp-gson-nextgen] Add oneOf support #10875 (comment)

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cc: @bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608

[wing328]

LGTM. Thanks for the enhancemenet.

[janisz]

@wing328 should I create backport PRs?

[wing328]

No. The upcoming release is 6.0.1 and there will be no more 5.x release.