Automatic merge from submit-queue (batch tested with PRs 55360, 56444, 56687, 56791, 56802). 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>.

certs: add month buckets to expiration metric

7 days isn't enough warning for cert expiration alerting.

#56444