feat(clustering): remove rpc of dynamic log level

[chronolaw]

Summary

KAG-5574
KAG-5749

After this PR spec/02-integration/18-hybrid_rpc/04-concentrator_spec.lua will be an empty test, we should finish it later.

Checklist

• The Pull Request has tests
• A changelog file has been created under changelog/unreleased/kong or skip-changelog label added on PR if changelog is unnecessary. README.md
• There is a user-facing docs PR against https://github.com/Kong/docs.konghq.com - PUT DOCS PR HERE

Issue reference

Fix #[issue number]

[team-gateway-bot]

Cherry-pick failed for master, because it was unable to cherry-pick the commit(s).

Please cherry-pick the changes locally.

git remote add upstream https://github.com/kong/kong-ee
git fetch upstream master
git worktree add -d .worktree/cherry-pick-13766-to-master-to-upstream upstream/master
cd .worktree/cherry-pick-13766-to-master-to-upstream
git checkout -b cherry-pick-13766-to-master-to-upstream
ancref=$(git merge-base 6cb8235b72052173fb484d85475b65f193a85831 a32e7912d094ef4b16cacf221e9f21a335227e9f)
git cherry-pick -x $ancref..a32e7912d094ef4b16cacf221e9f21a335227e9f