rolling_update: use ceph health instead of ceph -s

The ceph status command returns a lot of information stored in variables
and/or facts which could consume resources for nothing.
When checking the cluster health, we're using the health structure in the
ceph status output.
To optimize this, we could use the ceph health command which contains
the same needed information.

$ ceph status -f json | wc -c
2001
$ ceph health -f json | wc -c
46
Signed-off-by: Dimitri Savineau <dsavinea@redhat.com>
(cherry picked from commit acddf4fb)

infrastructure-playbooks/rolling_update.yml

@@ -136,8 +136,8 @@
 
     - block:
         - name: get ceph cluster status
-          command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} -s -f json"
-          register: check_cluster_status
+          command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} health -f json"
+          register: check_cluster_health
           delegate_to: "{{ mon_host }}"
 
         - block:
@@ -148,7 +148,7 @@
             - name: fail if cluster isn't in an acceptable state
               fail:
                 msg: "cluster is not in an acceptable state!"
-          when: (check_cluster_status.stdout | from_json).health.status == 'HEALTH_ERR'
+          when: (check_cluster_health.stdout | from_json).status == 'HEALTH_ERR'
       when: inventory_hostname == groups[mon_group_name] | first
 
     - name: ensure /var/lib/ceph/bootstrap-rbd-mirror is present