Automatic merge from submit-queue

Moves dns-horizontal-autoscaler to a separate service account

Similar to #38816.

As one of the cluster add-ons, dns-horizontal-autoscaler is now using the default service account in kube-system namespace, which is introduced by https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/e2e-rbac-bindings/random-addon-grabbag.yaml for the ease of transition. This default service account will be removed in the future.

This PR subdivides dns-horizontal-autoscaler to a separate service account and setup the necessary permissions.

@bowei 

**Release note**:

```release-note
NONE
```