feat: add csi-driver-nfs addon (#837)

template/templates/addons/csi-driver-nfs/app/helmrelease.yaml.j2

@@ -0,0 +1,30 @@
+---
+apiVersion: helm.toolkit.fluxcd.io/v2beta1
+kind: HelmRelease
+metadata:
+  name: csi-driver-nfs
+  namespace: kube-system
+spec:
+  interval: 30m
+  chart:
+    spec:
+      chart: csi-driver-nfs
+      version: v4.4.0
+      sourceRef:
+        kind: HelmRepository
+        name: csi-driver-nfs
+        namespace: flux-system
+  maxHistory: 2
+  install:
+    createNamespace: true
+    remediation:
+      retries: 3
+  upgrade:
+    cleanupOnFail: true
+    remediation:
+      retries: 3
+  uninstall:
+    keepHistory: false
+  values:
+    externalSnapshotter:
+      enabled: false