[Kotlin] Use array for generated annotation

[Zomzog]

This PR will fix #7799. I also add a generation sample with the delegate pattern for the Kotlin/Spring generation because it contains a lot of differences compared to the "classic" generation.

@jimschubert (2017/09) , @dr4ke616 (2018/08) @karismann (2019/03) @andrewemery (2019/10) @4brunu (2019/11) @yutaka0m (2020/03)

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[Zomzog]

The error has been fixed in another PR, this one still contains a new sample to follow changes with delegate patterns?

[wing328]

The new samples compile without issues 👍

I'll add it to the CI in another PR.