Automatic merge from submit-queue (batch tested with PRs 42042, 46139, 46126, 46258, 46312)
Remove kubectl's dependence on pkg/api/helper
**What this PR does / why we need it**:
Remove kubectl's dependence on pkg/api/helper, as part of
broader effort to isolate kubectl from the rest of k8s.
In this case, the code becomes private to kubectl; nobody else uses it.
**Which issue this PR fixes**
Part of a series of PRs to address kubernetes/community#598
**Release note**:
```release-note
NONE
```
Remove kubectl's dependence on pkg/api/helper, as part of
broader effort to isolate kubectl from the rest of k8s.
In this case, the code becomes private to kubectl; nobody else uses it.
**Which issue this PR fixes**
Part of a series of PRs to address kubernetes/community#598
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
