FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/core-js/internals/not-a-regexp.js

@@ -0,0 +1,10 @@
+'use strict';
+var isRegExp = require('../internals/is-regexp');
+
+var $TypeError = TypeError;
+
+module.exports = function (it) {
+  if (isRegExp(it)) {
+    throw new $TypeError("The method doesn't accept regular expressions");
+  } return it;
+};