This moves plugin/pkg/scheduler to pkg/scheduler and
plugin/cmd/kube-scheduler to cmd/kube-scheduler.
Bulk of the work was done with gomvpkg, except for kube-scheduler main
package.
Automatic merge from submit-queue (batch tested with PRs 53903, 53914, 54374). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Add PodDisruptionBudget to scheduler cache.
**What this PR does / why we need it**:
This is the first step to add support for PodDisruptionBudget during preemption. This PR adds PDB to scheduler cache.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**: None
**Release note**:
```release-note
Add PodDisruptionBudget to scheduler cache.
```
ref/ #53913
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Make scheduler integration test faster
Not to wait for 30 seconds for every negative test case. This commit
also organizes the test code to make it more readable.
It cuts the test time from 450s to 125s.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#53302
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```