Automatic merge from submit-queue (batch tested with PRs 67294, 67320, 67335, 67334, 67325). 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 wait to discovery integration test to fix flakiness

**What this PR does / why we need it**:
Reduce the flakiness of the discovery test that was introduced in #66932  (see cherry-pick PR #67154 for report on flaky failure and suggestions).

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

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```