Automatic merge from submit-queue (batch tested with PRs 56947, 56349, 57140, 53686, 57314). 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>.
admission_test.go(TestAdmitPreferNonmutating): simplify test
**What this PR does / why we need it**:
This PR simplifies `TestAdmitPreferNonmutating` test by inlining members that have a constant values.
**Release note**:
```release-note
NONE
```
PTAL @liggitt @tallclair
CC @simo5
b6b1762a80