Consider providing config option to specify PriorityClass

[leochr]

K8s resources (i.e. Deployments, StatefulSet, DaemonSet, Pod, Job/CronJob) allow the option to set PriorityClass to ensure that certain pods are not evicted (due to k8s preemption operations). Consider exposing this option via Liberty application CR.

https://devopscube.com/pod-priorityclass-preemption/

[BradleyMayo]

Initial PR for RCO here application-stacks/runtime-component-operator#626