Delete and renumber the TRG 3-2 to TRG 3-1 and remove superseded TRG for Kubernetes Version

[FaGru3n]

Hi all,

to update and have our TRG´s up-to-date, i would like to delete the superseded TRG 3-1

already created an issue and a PR for that #618

Please feel free to discuss and add your remarks on that within the PR.

Cheers @FaGru3n

[FaGru3n]

PR was already merged.