Automatic merge from submit-queue (batch tested with PRs 53337, 55465, 55512, 55522, 54554). 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>.
Don't clobber KUBE_VERBOSE in verify script
**What this PR does / why we need it**:
Don't clobber the KUBE_VERBOSE env var if set (but default it to 3 for the verify script if not set).
**Release note**:
```release-note
NONE
```