misc tracing span tweaks

Signed-off-by: Jason Volk <jason@zemos.net>

src/router/serve/unix.rs

@@ -30,7 +30,7 @@ type MakeService = IntoMakeServiceWithConnectInfo<Router, net::SocketAddr>;
 const NULL_ADDR: net::SocketAddr = net::SocketAddr::new(IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)), 0);
 const FINI_POLL_INTERVAL: Duration = Duration::from_millis(750);
 
-#[tracing::instrument(skip_all)]
+#[tracing::instrument(skip_all, level = "debug")]
 pub(super) async fn serve(server: &Arc<Server>, app: Router, mut shutdown: broadcast::Receiver<()>) -> Result<()> {
 	let mut tasks = JoinSet::<()>::new();
 	let executor = TokioExecutor::new();