Automatic merge from submit-queue (batch tested with PRs 58784, 62057, 62621, 62652, 62656). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
remove deprecated initresource admission plugin
**What this PR does / why we need it**:
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
xref https://github.com/kubernetes/kubernetes/pull/55375#issuecomment-360329586
**Special notes for your reviewer**:
/assign @piosz @deads2k
**Release note**:
```release-note
remove deprecated initresource admission plugin
```
