Add staging layout

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

hub/staging.yaml

@@ -0,0 +1,23 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: staging
+---
+apiVersion: kustomize.toolkit.fluxcd.io/v1
+kind: Kustomization
+metadata:
+  name: cluster-sync
+  namespace: staging
+spec:
+  interval: 1h
+  retryInterval: 3m
+  timeout: 5m
+  prune: true
+  wait: true
+  path: ./clusters/staging
+  sourceRef:
+    kind: GitRepository
+    name: flux-system
+  kubeConfig:
+    secretRef:
+      name: cluster-kubeconfig