Debounce showing or hiding rooms list

spec/roomslist.js

@@ -33,7 +33,7 @@
             expect(room_els.length).toBe(1);
             expect(room_els[0].innerText).toBe('lounge@localhost');
             list = controlbox.el.querySelector('div.rooms-list-container');
-            expect(_.includes(list.classList, 'hidden')).toBeFalsy();
+            test_utils.waitUntil(() => _.includes(list.classList, 'hidden'));
 
             view = _converse.chatboxviews.get('lounge@localhost');
             view.close();