Groovy formatting with Spotless leaves a temporary directory

[baloo42]

Is your task related to a problem? Please describe

There is currently a bug in the spotless groovy formatter which affects this project: Spotless leaves a temporary directory on each formatter execution.

https://github.com/diffplug/spotless/issues/2019

Introduced with PR https://github.com/fabric8io/kubernetes-client/pull/6301

Describe the solution you'd like

All temporary directories are cleaned up after an execution.

Describe alternatives you've considered

No response

Additional context

First discussed here: https://github.com/fabric8io/kubernetes-client/pull/5979#discussion_r1664383998

we can try and live with this for now. If it gets annoying we can disable.