Spawn async jobs in ntex

[photino]

How can we run async jobs in the background? I have tried

System::new("scheduler")
    .system()
    .arbiter()
    .spawn(Box::pin(async move {
        loop {
            scheduler.tick().await;

            // Cannot use `std::thread::sleep` because it blocks the Tokio runtime.
            time::sleep(scheduler.time_till_next_job()).await;
        }
    }));

But it does not work as expected.

Also see ntex-rs/ntex#335 (comment)