Stream can be safely dispose

[bierquelle06]

Depending on where the Stream object comes from, you need to be aware of whether the caller is responsible for disposing of the stream after creating the FirebasePushNotificationSender instance.

Solution: Clearly document in the constructor's documentation or method signature who is responsible for disposing of the stream. If the caller is responsible, provide guidance on when the stream can be safely disposed.

Can be help to this code block :

public FirebasePushNotificationSender(Stream stream)
{
using (stream)
{
var firebaseApp = FirebaseApp.Create(new AppOptions()
{
Credential = GoogleCredential.FromStream(stream)
});

this._firebaseMessaging = FirebaseMessaging.GetMessaging(firebaseApp);
}
}