*Service Worker detect new build and prompt user to reload.

*To get Notification: FCM- Firebase cloud messaging. Realtime-db, collection-fcmTokens,user001

POST: https://fcm.googleapis.com/fcm/send body: {"notification": { "title": "Hello", "body": "This is Message to firebase" }, "to" : "dJWQc2bFUxSs1lfaA23WK7:APA91bGMYOOBcaQm0IWtPy1lZ0Zui0awmvYQZR6V9woN-0VKZ4o3lY67alp3U-xa0Cl5W86ioyLtnDgdcZ33eh58eraQRkHa63MMortLDNDR5pTlaab6FChzB3SksKWDngQxCZ2B1kpa" }