Automatic merge from submit-queue (batch tested with PRs 62984, 64304). 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 alpha feature warning for log rotation flags.
CRI container log rotation is beta now.
@yujuhong /cc @mtaufen @kubernetes/sig-node-pr-reviews
Signed-off-by: Lantao Liu <lantaol@google.com>
**Release note**:
```release-note
none
```