templates: add After=ostree-finalize-staged.service to kubelet.service

We've seen occasional issues during upgrades caused by what seems to be
the kubelet still being active during OSTree finalization. If the
kubelet changes things in `/etc`, it'll confuse OSTree which is trying
to do the `/etc` merge.

We want to be sure that the kubelet is done modifying everything it
needs to in `/etc` and that it exited before we finalize the deployment.

Add a `After=ostree-finalize-staged.service` for this. The way this
works is that that service runs in its `ExecStop`, and shutdown ordering
is the reverse of startup. So this will cause the kubelet to exit before
`ostree-finalize-staged.service` is stopped.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1902963

templates/master/01-master-kubelet/_base/units/kubelet.service.yaml

@@ -5,6 +5,7 @@ contents: |
   Description=Kubernetes Kubelet
   Wants=rpc-statd.service network-online.target crio.service
   After=network-online.target crio.service
+  After=ostree-finalize-staged.service
 
   [Service]
   Type=notify

templates/master/01-master-kubelet/baremetal/units/kubelet.service.yaml

@@ -5,6 +5,7 @@ contents: |
   Description=Kubernetes Kubelet
   Wants=rpc-statd.service network-online.target crio.service
   After=network-online.target crio.service
+  After=ostree-finalize-staged.service
 
   [Service]
   Type=notify

templates/worker/01-worker-kubelet/_base/units/kubelet.service.yaml

@@ -5,6 +5,7 @@ contents: |
   Description=Kubernetes Kubelet
   Wants=rpc-statd.service network-online.target crio.service
   After=network-online.target crio.service
+  After=ostree-finalize-staged.service
 
   [Service]
   Type=notify

templates/worker/01-worker-kubelet/baremetal/units/kubelet.service.yaml

@@ -5,6 +5,7 @@ contents: |
   Description=Kubernetes Kubelet
   Wants=rpc-statd.service network-online.target crio.service
   After=network-online.target crio.service
+  After=ostree-finalize-staged.service
 
   [Service]
   Type=notify