pub async fn spawn_server(
__arg0: ConfigMetrics,
gather_metrics: impl Fn() -> Bytes + Clone + Send + 'static,
is_health_check: impl Fn() -> bool + Clone + Send + 'static,
is_ready_check: impl Fn() -> bool + Clone + Send + 'static,
shutdown: impl Future<Output = ()> + Send + 'static,
) -> Result<impl Future<Output = Result<(), JoinError>>>