Only setup backup when rsnapshot is configured, don't use password for root auth

mysql/tasks/main.yml

@@ -24,30 +24,15 @@
     state: started
     enabled: true
 
-- name: ensure the mysql root user exists and has the correct password
-  mysql_user:
-    name: root
-    password: "{{ mysql_root_password }}"
-    login_user: root
-    login_password: "{{ mysql_root_password }}"
-  register: mysql_root_creation_result
-  no_log: true
-  ignore_errors: true
-
-- name: initialize the mysql root user
-  mysql_user:
-    name: root
-    password: "{{ mysql_root_password }}"
-  no_log: true
-  when: mysql_root_creation_result is failed
-
+- name: setup mysql backups with rsnapshot
+  when: '"servers_rsnapshot" in group_names'
+  block:
     - name: ensure a read-only mysql user for backups exists
       mysql_user:
         name: "{{ mysql_backup_user }}"
         password: "{{ mysql_backup_password }}"
-    login_user: root
-    login_password: "{{ mysql_root_password }}"
         priv: "*.*:SELECT,LOCK TABLES"
+      no_log: true
 
     - name: ensure the backup procedure can access the backup password
       template: