fix: Skip post-install hooks for rancher-backup HelmRelease

The chart's post-install hook uses rancher/kuberlr-kubectl which fails
to download kubectl. The SA automountServiceAccountToken is managed
manually, so the hook is unnecessary.

infrastructure/addons/rancher-backup/helmrelease-rancher-backup.yaml

@@ -20,9 +20,11 @@ spec:
     createNamespace: true
     remediation:
       retries: 3
+    skipHooks: true
   upgrade:
     remediation:
       retries: 3
+    skipHooks: true
   values:
     image:
       repository: rancher/backup-restore-operator