Fix default dest for main config

tasks/main.yml

@@ -8,7 +8,7 @@
 - name: MySQL | Deploy main config
   template:
     src:   "{{ mysql_main_conf.src }}"
-    dest:  "{{ mysql_main_conf.dest }}"
+    dest:  "{{ mysql_main_conf.dest | d('/etc/my.cnf') }}"
     mode:  "{{ mysql_configs_mode }}"
     owner: "{{ mysql_configs_user }}"
     group: "{{ mysql_configs_user }}"