Fix typo

src/js/main.js

@@ -97,7 +97,7 @@ angular.module('Application').controller('MainController', ['$scope', '$route',
                 actionScope.action = '/#/backups';
 
                 Client.notify('Backup Configuration',
-                    'Cloudron backups are currently on the same disk as the Cloudron server instance. This is dangerous and can lead to complete data loss if the disk fails.' +
+                    'Cloudron backups are currently on the same disk as the Cloudron server instance. This is dangerous and can lead to complete data loss if the disk fails.',
                     false /* persistent */, 'info', actionScope);
             }
         });