Fix tests

app/controllers/application.js

@@ -1,7 +1,7 @@
 import Controller from '@ember/controller';
 import { inject as service } from '@ember/service';
 import { alias } from '@ember/object/computed';
-import { observer, computed } from '@ember/object';
+import { observer } from '@ember/object';
 
 export default Controller.extend({
 
@@ -26,5 +26,4 @@ export default Controller.extend({
     });
   }
 
-
 });