Automatic merge from submit-queue
Adding a metadata proxy addon
**What this PR does / why we need it**: adds a metadata server proxy daemonset to hide kubelet secrets.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: this partially addresses #8867
**Special notes for your reviewer**:
**Release note**: the gce metadata server can be hidden behind a proxy, hiding the kubelet's token.
```release-note
The gce metadata server can be hidden behind a proxy, hiding the kubelet's token.
```