Add part-of label to the static manifests

Signed-off-by: Stefan Prodan <stefan.prodan@gmail.com>

manifests/install/labels.yaml

@@ -3,6 +3,7 @@ kind: LabelTransformer
 metadata:
   name: labels
 labels:
+  app.kubernetes.io/part-of: flux
   app.kubernetes.io/instance: flux-system
 fieldSpecs:
   - path: metadata/labels