Automatic merge from submit-queue (batch tested with PRs 51819, 51706, 51761, 51818, 51500)
fix kube-proxy panic because of nil sessionAffinityConfig
**What this PR does / why we need it**:
fix kube-proxy panic because of nil sessionAffinityConfig
**Which issue this PR fixes**: closes#51499
**Special notes for your reviewer**:
I apology that this bug is introduced by #49850 :(
@thockin @smarterclayton @gnufied
**Release note**:
```release-note
NONE
```