Automatic merge from submit-queue (batch tested with PRs 58144, 57149). 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>.

make quota reusable

Quota is logically a re-useable component so that replenishment and admission can be done in constituent servers.  This makes it possible to embed.  More cleanup is probably required, but this is the minimum.