switch: make osd collection idempotent

This commits allows us to run
switch-from-non-containerized-to-containerized-ceph-daemons.yml multiple
times.

Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1489353
Signed-off-by: Sébastien Han <seb@redhat.com>

infrastructure-playbooks/switch-from-non-containerized-to-containerized-ceph-daemons.yml

@@ -199,6 +199,7 @@
         systemctl list-units | grep "loaded active" | grep -Eo 'ceph-osd@[0-9]{1,2}.service'
       register: running_osds
       changed_when: false
+      failed_when: false
 
     - name: collect osd devices
       shell: |
@@ -222,7 +223,8 @@
         state: stopped
         enabled: no
         masked: yes
-      with_items: "{{ running_osds.stdout_lines }}"
+      with_items: "{{ running_osds.stdout_lines | default([])}}"
+      when: running_osds != []
 
     - set_fact:
         ceph_uid: 64045