[JAVA] okhttp-gson client codegen ambiguous references for a component schema "Type"

[farnulfo]

PR to fix #19326 by removing unnecessary line "import java.lang.reflect.Type" in pojo.mustache that cause collision with a "Type" defined in a OpenAPI spec.

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[farnulfo]

Hi,

@bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

Here is a PR to fix #19326 but it's missing the test case: I don't know how to add it.
It's an OpenAPI file that contains a Type component that cause compilation errors with okhttp-gson generated code because of an "import java.lang.reflect.Type" in pojo.mustache template that is not necessary.

Happy to add it with your help.

[martin-mfg]

Hi @farnulfo, thanks for the PR! I think it's fine without a dedicated test case.

[wing328]

don't recall the exact reason why it's added in the first place.

if this breaks any other use cases somehow, we will need to roll back this fix and use model name mapping option instead: https://github.com/openapitools/openapi-generator/blob/master/docs/customization.md#name-mapping