Automatic merge from submit-queue. 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>.
code-gen: output golint compliant 'Generated by' comment
New PR instead of reopening #58115 because /reopen did not work.
This won't be ready to merge until the upstream https://github.com/kubernetes/gengo/pull/94 merges. Once that merges, the second commit will be changed to godep-save.sh and update-staging-godeps.sh, and the last commit will be changed to update-all.sh
The failing test is due to the upstream changes not being merged yet
```devel-release-note
Go code generated by the code generators will now have a comment which allows them to be easily identified by golint
```
Fixes#56489
Kubernetes-commit: 1eb1c00c44f8f597b9b23a05cd0a8da205c87f8a
Automatic merge from submit-queue. 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>.
staging: add boilerplate header
Follow up of https://github.com/kubernetes/kubernetes/pull/57656.
Adds boilerplate in the relevant staging repos so that they don't need to depend on code-generator's boilerplate.
**Release note**:
```release-note
NONE
```
/cc sttts fisherxu
Kubernetes-commit: 1a1643bb5df07d94330e1b16d182cee660533f91
Automatic merge from submit-queue. 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>.
Update gengo version to include goimports formatter
Update gengo which now uses goimports to format code and organize imports.
Fixes#55542
**Special notes for your reviewer**:
Updates version of k8s.io/gengo
Takes new dependency on golang.org/x/tools/imports and golang.org/x/tools/go/ast/astutil
**Release Notes**:
```release-note
NONE
```
Kubernetes-commit: 46eabb7d918d962a9c8e0474d41f9371081d47fa