Automatic merge from submit-queue (batch tested with PRs 49850, 47782, 50595, 50730, 51341)
Paramaterize `stickyMaxAgeMinutes` for service in API
**What this PR does / why we need it**:
Currently I find `stickyMaxAgeMinutes` for a session affinity type service is hard code to 180min. There is a TODO comment, see
https://github.com/kubernetes/kubernetes/blob/master/pkg/proxy/iptables/proxier.go#L205
I think the seesion sticky max time varies from service to service and users may not aware of it since it's hard coded in all proxier.go - iptables, userspace and winuserspace.
Once we parameterize it in API, users can set/get the values for their different services.
Perhaps, we can introduce a new field `api.ClientIPAffinityConfig` in `api.ServiceSpec`.
There is an initial discussion about it in sig-network group. See,
https://groups.google.com/forum/#!topic/kubernetes-sig-network/i-LkeHrjs80
**Which issue this PR fixes**:
fixes#49831
**Special notes for your reviewer**:
**Release note**:
```release-note
Paramaterize session affinity timeout seconds in service API for Client IP based session affinity.
```
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