When you trying to login in Test env, and it does not show any error (you was returned on login form again), and you does not have anything in logs, except Guard authenticator does not support the request. {"firewall_key":"main","authenticator":"App\\Security\\AppAuthenticator"}, you can try this.
I removed lines:
session:
storage_id: session.storage.mock_file
in config/packages/test/framework.yaml and it worked