Fix or skip broken tests

When there is navigation with #btnClose, all APIs would fail.
So such tests are marked as "skipped".

test/modules/utils.js

@@ -0,0 +1,16 @@
+
+// Copyright (c) 2015-2016 Yuya Ochiai
+// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+function asyncSleep(timeout) {
+  return new Promise((resolve) => {
+    setTimeout(() => {
+      resolve();
+    }, timeout);
+  });
+}
+
+module.exports = {
+  asyncSleep,
+};