Add Push Notifications to a PWA with React in Chrome and on Android

On Android and in Chrome (but not on iOS), it's possible to send push notifications with a PWA. We'll start by asking the user for permission to send them push notifications, and then look at how to intercept the push event in a service worker. We can test the push notifications directly in Chrome's devtools, and we will also make a button that can trigger a push notification directly from the PWA app code itself.