Upgrade: Longhorn from 1.5.2 to 1.6.4

Change-Id: I8cdc3c0a07133f00442b496800ccc30e2c1dad61
diff --git a/charts/longhorn/templates/network-policies/instance-manager-networking.yaml b/charts/longhorn/templates/network-policies/instance-manager-networking.yaml
index 6f03c6e..332aa2c 100644
--- a/charts/longhorn/templates/network-policies/instance-manager-networking.yaml
+++ b/charts/longhorn/templates/network-policies/instance-manager-networking.yaml
@@ -3,7 +3,7 @@
 kind: NetworkPolicy
 metadata:
   name: instance-manager
-  namespace: longhorn-system
+  namespace: {{ include "release_namespace" . }}
 spec:
   podSelector:
     matchLabels: