fix(go): properly generate inline enums

[sruehl]

Fixes #9567

The PR added a unit test to demonstrate missing enums as defined in #9567. To validate one can uncomment line 117 in GoClientCodegen.java and then the tests will fail.

@antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5

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[sruehl]

set to draft for now as it seems that at the moment Enum names collide. This is not unique to inline enums so I wonder how that is solved in general. Any ideas how to fix that @antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5?

[sruehl]

also on the note of a "breaking" change. It is breaking and kind of not: The enums have the base type as before so from a user perspective a missing cast is required if the base types are being used. The non-breaking part is that it is still the same more or less. For that reason I was unsure if it is now breaking or non breaking.