Include statefulsets description and its behavior during a node NotReady state.
As of now there are no much data available about the Statefulsets and its default behavior in the official OCP documentation.

Business Impact:
- CU recently had an issue with the nodes where the nodes went to NotReady state and the statefulsets didn't actually rescheduled. 
- According to the Official Openshift documentation the pods should reschedule to another working node once the tolerationtime in seconds are finished according to the documentation here[0]
- But there is some manual intervention required to get the pods evicted and to get rescheduled into other nodes in case of Statefulsets and itsan expected behavior.
- We have already this[1] upstream doc and a KCS[2] which actually describes the same and are the fundamental behavior of the same.
- But it would be great if we could add the same as a note in the OCP documentation[0] as it already includes the information for the daemon-sets pods behavior


[0] https://docs.openshift.com/container-platform/4.12/nodes/scheduling/nodes-scheduler-taints-tolerations.html#nodes-scheduler-taints-tolerations-about-taintBasedEvictions_nodes-scheduler-taints-tolerations
[1] https://kubernetes.io/docs/tasks/run-application/force-delete-stateful-set-pod/#delete-pods
[2] https://access.redhat.com/solutions/4254721

4.12

- Run a statefulset deployment
- Make a node notReady where one of the statefulset pod runs
- The statefulset pod will not automatically reschedule to another node
- We may need to manually remove the pod which is marked for deletion and then reschedule it

1.
2.
3.

The STS pods are not rescheduled to a working node without manual interventions.

Need to add the same into the documentation that this is the expected behavior in case of STS pods! 

Reference Case: 03460040