for version 12.3.0
"com.google.firebase.remote-config": "https://github.com/firebase-unity/firebase-remote-config.git#12.3.0",dependency firebase-app 12.3.0, external-dependency-manager 1.2.183
"com.google.firebase.app": "https://github.com/firebase-unity/firebase-app.git#12.3.0",
"com.google.external-dependency-manager": "https://github.com/google-unity/external-dependency-manager.git#1.2.183",