FCM deprecated HTTP legacy send API

[Vibha-BLL]

See the migration instructions here: https://firebase.google.com/docs/cloud-messaging/migrate-v1

HTTP requests before:

POST https://fcm.googleapis.com/fcm/send
After:

POST https://fcm.googleapis.com/v1/projects/myproject-b5ae1/messages:send

DefaultEndpoint = "https://fcm.googleapis.com/fcm/send"
Are there plans to update this Endpoint in the library?