Automatic merge from submit-queue (batch tested with PRs 47232, 48625, 48613, 48567, 39173)

Make kube-proxy's MetricsBindAddress configurable via flag

**What this PR does / why we need it**: From #48600, `MetricsBindAddress` used to be configurable through flag (coupled with `HealthzBindAddress`). But this functionality went away after #44968 separated healthz server from metrics server. This PR adds that functionality back.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: 

**Special notes for your reviewer**:
/assign @ncdc 
cc @bowei @r0bj

**Release note**:

```release-note
none
```