update: convert legacy grafana-server groupname early

If the legacy name `grafana-server` is still being used when upgrading
from Nautilus to Pacific, the task that sets the fact `rolling_update`
to `true` doesn't run on the node(s) included in that group. Indeed the
play where we set this fact (`rolling_update`) only runs on the group
`monitoring_group_name | default('monitoring')`.
As a workaround, we can run earlier the task which converts the
`grafana-server` group name to `monitoring`.

Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1935554

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>
(cherry picked from commit 6ccc8b4722)

infrastructure-playbooks/rolling_update.yml

@@ -36,6 +36,16 @@
            invoking the playbook"
       when: ireallymeanit != 'yes'
 
+    - name: import_role ceph-defaults
+      import_role:
+        name: ceph-defaults
+
+    - name: check if a legacy grafana-server group exists
+      import_role:
+        name: ceph-facts
+        tasks_from: convert_grafana_server_group_name.yml
+      when: groups.get((grafana_server_group_name | default('grafana-server')), []) | length > 0
+
 
 - name: gather facts and check the init system