[FR] Support Apple's location push type

**Is your feature request related to a problem? Please describe.**
Since iOS 15 was introduced by Apple we would like to support their new location push notification. FCM currently returns an error because it doesn't support the type.

**Describe the solution you'd like**
FCM supporting the new location push type.

**Describe alternatives you've considered**
Implementing the sending of location remote notifications on our own which disruptes the centralized way of how we send remote notifications.

**Additional context**
- [Apple's documentation](https://developer.apple.com/documentation/corelocation/cllocationmanager/creating_a_location_push_service_extension#overview) - see under _Send Location Push Requests From Your Server_
- [GitHub Issue](https://github.com/firebase/firebase-admin-java/issues/607#issuecomment-1003143660) related incl. discussion with @chliangGoogle
- Firebase Feature Request Number: `10155562`