fix defaults

defaults/main.yml

@@ -28,6 +28,6 @@ gitlab:
     auto_link_ldap_user: 'true'
     providers: []
   upload_size_max: 128M
-  mail: {}
-    #from: 'git@domain'
-    #reply_to: 'git@domain'
+  mail:
+    from: ~
+    reply_to: ~