message: Fix GroupView test
  It was counting the wrong number of updates for reasons I don't understand.
diff: @@ -302,7 +302,7 @@ describe('GroupView', function() {
  it('should show a RoomDetailList after a successful /summary & /rooms (no rooms returned)', function() {
  const groupView = ReactTestUtils.findRenderedComponentWithType(root, GroupView);
  - const prom = waitForUpdate(groupView, 5).then(() => {
  + const prom = waitForUpdate(groupView, 4).then(() => {
  const roomDetailList = ReactTestUtils.findRenderedDOMComponentWithClass(root, 'mx_RoomDetailList');
  const roomDetailListElement = ReactDOM.findDOMNode(roomDetailList);
  expect(roomDetailListElement).toBeTruthy();
  