[bootstrap] feat: target cluster ansible plays only to kubernetes in case other hosts are used (#1065)

bootstrap/templates/ansible/playbooks/cluster-rollout-update.yaml.j2

@@ -1,7 +1,7 @@
 ---
 # https://github.com/kevincoakley/ansible-role-k8s-rolling-update
 - name: Cluster rollout update
-  hosts: all
+  hosts: kubernetes
   become: true
   gather_facts: true
   any_errors_fatal: true