Merge pull request #59837 from Cynerva/gkk/fix-auth-bootstrap-on-upgrade

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

juju: Fix broken ingress after upgrade-charm

**What this PR does / why we need it**:

This fixes a bug that prevents the ingress controller from being deployed after doing an `upgrade-charm`.

Essentially, `worker.auth.bootstrapped` gets cleared during `upgrade-charm`, and it never gets set again. This prevents the `start_worker` and `render_and_launch_ingress` handlers from running, among other things.

This PR fixes that.

**Release note**:

```release-note
NONE
```

cluster/juju/layers/kubernetes-worker/reactive/kubernetes_worker.py

@@ -970,15 +970,14 @@ def catch_change_in_creds(kube_control):
     """Request a service restart in case credential updates were detected."""
     nodeuser = 'system:node:{}'.format(get_node_name().lower())
     creds = kube_control.get_auth_credentials(nodeuser)
-    if creds \
-            and data_changed('kube-control.creds', creds) \
-            and creds['user'] == nodeuser:
+    if creds and creds['user'] == nodeuser:
         # We need to cache the credentials here because if the
         # master changes (master leader dies and replaced by a new one)
         # the new master will have no recollection of our certs.
         db.set('credentials', creds)
         set_state('worker.auth.bootstrapped')
-        set_state('kubernetes-worker.restart-needed')
+        if data_changed('kube-control.creds', creds):
+            set_state('kubernetes-worker.restart-needed')
 
 
 @when_not('kube-control.connected')