def METHOD_NAME(create_command, first_app_config):
    """Error if App config is missing the runtime."""
    first_app_config.flatpak_runtime_version = "37.42"
    first_app_config.flatpak_sdk = "org.beeware.SDK"
    with pytest.raises(
        BriefcaseConfigError,
        match="Briefcase configuration error: The App does not specify the Flatpak runtime to use",
    ):
        create_command.flatpak_runtime(first_app_config)