add actionable error message for TimeoutError in hooks. (#4053)

* added a help message in case when async hook timesout.

* updated help message

Co-authored-by: Priyansh Garg <priyanshgarg30@gmail.com>

---------

Co-authored-by: Priyansh Garg <priyanshgarg30@gmail.com>

lib/testsuite/hooks/_basehook.js

@@ -62,6 +62,7 @@ class BaseHook {
       return new Promise((resolve, reject) => {
         try {
           const timedCallback = this.createCallbackWrapper(resolve, reject, err => {
+            err.help = ['You can increase the hooks timeout by setting "asyncHookTimeout" in the globals config to the required value.'];
             err.skipTestCases = this.skipTestcasesOnError;
             runnableDone && runnableDone(err);
             reject(err);
@@ -151,7 +152,7 @@ class BaseHook {
    * @return {TimedCallback}
    */
   createCallbackWrapper(resolve, reject, timeoutExpired) {
-    let timedCallback = new TimedCallback(function doneCallback(err) {
+    const timedCallback = new TimedCallback(function doneCallback(err) {
       if (Utils.isErrorObject(err)) {
         return reject(err);
       }