GoogleService-Info.plist file not found and clientId was not provided programmatically.

[Tobi696]

I have configured my flutter app using flutterfire_cli. In Firebase, I have enabled Authentication via Google.
As google_sign_in doesn't support dart only initialization yet, I have also added the GoogleService-Info.plist file to my Runner xcodeproject.

However, when I call GoogleSignIn().signIn(), I get missing-config with GoogleService-Info.plist file not found and clientId was not provided programmatically.
Currently, I am initializing Firebase with the options: DefaultFirebaseOptions.currentPlatform parameter, but I also tried it without the options parameter, but the result stays the same.
I don't know what I should do to fix it, I even have another project where that doesn't have firebase_core in its dependencies and so never calls initializeApp(), but the google sign in works on that project...