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>.

When cert dir is relative, cert rotation builds incorrect symlinks

Symlinks relative to a working directory were being constructed to the
wrong location, leading to failure to refresh client certs.

@liggitt