feat(push notifications): test implemintation of push notifcations

lib/core/firebase_api.dart

@@ -0,0 +1,11 @@
+import 'package:firebase_messaging/firebase_messaging.dart';
+
+class FirebaseApi {
+
+  final _firebaseMessaging = FirebaseMessaging.instance;
+
+  Future<String?> getToken() async{
+    await _firebaseMessaging.requestPermission();
+    return await _firebaseMessaging.getToken();
+  }
+}