add deletecollection verb (#589)

Fixing privileges to execute `patronictl remove`.

You could/should have also just used the operator delete cluster flow (remove manifest). It is not really the plan to use patroni inside a pod to remove a existing cluster.

charts/postgres-operator/templates/clusterrole.yaml

@@ -43,6 +43,7 @@ rules:
   verbs:
   - create
   - delete
+  - deletecollection
   - get
   - list
   - patch

manifests/operator-service-account-rbac.yaml

@@ -40,6 +40,7 @@ rules:
   verbs:
   - create
   - delete
+  - deletecollection
   - get
   - list
   - patch