Automatic merge from submit-queue
Moved qos to api.helpers.
**What this PR does / why we need it**:
The `GetPodQoS` is also used by other components, e.g. kube-scheduler and it's not bound to kubelet; moved it to api helpers so client-go.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #N/A
**Release note**:
```release-note-none
```