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>.
allow fail close webhook admission
Webhook admission needs to allow failing closed. Even in an alpha state, I don't want to be one DDOS away from having an exposed cluster.
/assign caesarxuchao
/assign sttts