Automatic merge from submit-queue (batch tested with PRs 50381, 51307, 49645, 50995, 51523)

Update defaults.go

**What this PR does / why we need it**:
This PR is a TODO
Add explain about TaintTolerationPriority function.

**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**:

**Release note**:

```release-note
NONE
```