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>.
kubeadm - set peer urls for default etcd instance
**What this PR does / why we need it**:
Override the default peer URLs for the default etcd instance. Previously we left the defaults, which meant the peer URL was unsecured previously.
**Release note**:
```release-note
kubeadm - Ensure the peer port is secured by explicitly setting the peer URLs for the default etcd instance.
kubeadm - Ensure that the etcd certificates are generated using a proper CN
kubeadm - Update generated etcd peer certificate to include localhost addresses for the default configuration.
kubeadm - Increase the manifest update timeout to make upgrades a bit more reliable.
```