feat(longhorn): Add priorityClass to critical components

This patch should help to make sure that longhorn gets the priority
scheduling in the cluster.

References:
https://kubernetes.io/docs/concepts/scheduling-eviction/pod-priority-preemption/#priorityclass
https://longhorn.io/docs/1.2.3/references/settings/#priority-class

infrastructure/longhorn/release.yaml

@@ -23,6 +23,10 @@ spec:
         systemDefaultRegistry: docker.io
     persistence:
       defaultClassReplicaCount: 2
+    longhornManager:
+      priorityClass: system-cluster-critical
+    longhornDriver:
+      priorityClass: system-cluster-critical
   postRenderers:
     # Instruct helm-controller to use built-in "kustomize" post renderer.
     - kustomize: