on PVC when_scaled:retain check pod count, too (#2415)

* on PVC when_scaled:retain check pod count and wait for replica label

Author: FxKu

e2e/tests/test_e2e.py

@@ -1254,11 +1254,13 @@ def test_persistent_volume_claim_retention_policy(self):
         k8s.api.custom_objects_api.patch_namespaced_custom_object(
             'acid.zalan.do', 'v1', 'default', 'postgresqls', 'acid-minimal-cluster', pg_patch_scale_down_instances)
         self.eventuallyEqual(lambda: k8s.get_operator_state(), {"0": "idle"},"Operator does not get in sync")
+        self.eventuallyEqual(lambda: k8s.count_running_pods(), 1, "Scale down to 1 failed")
         self.eventuallyEqual(lambda: k8s.count_pvcs_with_label(cluster_label), 2, "PVCs is deleted when scaled down")
 
         k8s.api.custom_objects_api.patch_namespaced_custom_object(
             'acid.zalan.do', 'v1', 'default', 'postgresqls', 'acid-minimal-cluster', pg_patch_scale_up_instances)
         self.eventuallyEqual(lambda: k8s.get_operator_state(), {"0": "idle"},"Operator does not get in sync")
+        k8s.wait_for_pod_start('spilo-role=replica,' + cluster_label)
         self.eventuallyEqual(lambda: k8s.count_pvcs_with_label(cluster_label), 2, "PVCs is not equal to number of instances")
 
     @timeout_decorator.timeout(TEST_TIMEOUT_SEC)