lint: fix error [301], add `changed_when: false` when needed

This commit fixes the error [301]:

`[301] Commands should not change things if nothing needs doing`

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>

roles/ceph-dashboard/tasks/configure_dashboard.yml

@@ -62,6 +62,7 @@
 
 - name: "set the dashboard port ({{ dashboard_port }})"
   command: "{{ container_exec_cmd }} ceph config set mgr mgr/dashboard/server_port {{ dashboard_port }}"
+  changed_when: false
   delegate_to: "{{ groups[mon_group_name][0] }}"
   run_once: true
 
@@ -69,6 +70,8 @@
   command: "{{ container_exec_cmd }} ceph config set mgr mgr/dashboard/ssl_server_port {{ dashboard_port }}"
   delegate_to: "{{ groups[mon_group_name][0] }}"
   run_once: true
+  changed_when: false
+  failed_when: false # Do not fail if the option does not exist, it only exists post-14.2.0
 
 - name: disable mgr dashboard module (restart)
   command: "{{ container_exec_cmd }} ceph mgr module disable dashboard"
@@ -94,6 +97,7 @@
   register: ac_result
   delegate_to: "{{ groups[mon_group_name][0] }}"
   run_once: true
+  changed_when: false
   until: ac_result.rc == 0
 
 - name: set grafana url

roles/ceph-mgr/tasks/mgr_modules.yml

@@ -10,6 +10,7 @@
   retries: 30
   delay: 5
   delegate_to: "{{ groups[mon_group_name][0] }}"
+  changed_when: false
   until:
     - mgr_dump.rc == 0
     - (mgr_dump.stdout | from_json).available | bool