* Upgrading playwright to 1.21
Also, locking CI to install 1.21 (just like package.json is using).
This way, on the next Playwright release, CI will continue working.
* Running npx install playwright from the tests directory so that playwright can install the correct browsers
Now, if the first pusher request fails, a waiting message will be displayed and the application will reconnect when the pusher comes back alive or the network connection is established again.