feat: move kubernetes dir into templates to support jinja2 across all files (#831)

template/templates/kubernetes/apps/flux-system/addons/webhooks/github/receiver.yaml.j2

@@ -0,0 +1,26 @@
+---
+apiVersion: notification.toolkit.fluxcd.io/v1
+kind: Receiver
+metadata:
+  name: github-receiver
+  namespace: flux-system
+spec:
+  type: github
+  events:
+    - ping
+    - push
+  secretRef:
+    name: github-webhook-token-secret
+  resources:
+    - apiVersion: source.toolkit.fluxcd.io/v1
+      kind: GitRepository
+      name: home-kubernetes
+      namespace: flux-system
+    - apiVersion: kustomize.toolkit.fluxcd.io/v1
+      kind: Kustomization
+      name: cluster
+      namespace: flux-system
+    - apiVersion: kustomize.toolkit.fluxcd.io/v1
+      kind: Kustomization
+      name: cluster-apps
+      namespace: flux-system