[Update] GooglePlayServices need to be updated for Xamarin.Firebase.Messaging

[Phenek]

Here the conflict:

Version conflict detected for Xamarin.GooglePlayServices.Base. Install/reference Xamarin.GooglePlayServices.Base 71.1610.0 directly to project projX.Android to resolve this issue. 
 projX.Android -> Xamarin.Firebase.Messaging 71.1740.0 -> Xamarin.Firebase.Iid 71.1710.0 -> Xamarin.Firebase.Iid.Interop 71.1601.0 -> Xamarin.GooglePlayServices.Base (>= 71.1610.0) 
projX.Android -> UnifiedMaps 2.0.3 -> Xamarin.GooglePlayServices.Maps 60.1142.1 -> Xamarin.GooglePlayServices.Base (= 60.1142.1).
```

[Phenek]

#105 here the PR