Improve tokio task execution (#1181)

* Add logging on shutdown

* Replace tokio::spawn with handle.spawn

* Upgrade tokio

* Add a task executor

* Beacon chain tasks use task executor

* Validator client tasks use task executor

* Rename runtime_handle to executor

* Add duration histograms; minor fixes

* Cleanup

* Fix logs

* Fix tests

* Remove random file

* Get enr dependency instead of libp2p

* Address some review comments

* Libp2p takes a TaskExecutor

* Ugly fix libp2p tests

* Move TaskExecutor to own file

* Upgrade Dockerfile rust version

* Minor fixes

* Revert "Ugly fix libp2p tests"

This reverts commit 58d4bb690f.

* Pretty fix libp2p tests

* Add spawn_without_exit; change Counter to Gauge

* Tidy

* Move log from RuntimeContext to TaskExecutor

* Fix errors

* Replace histogram with int_gauge for async tasks

* Fix todo

* Fix memory leak in test by exiting all spawned tasks at the end

beacon_node/eth1/src/service.rs

@@ -290,7 +290,7 @@ impl Service {
     /// - Err(_) if there is an error.
     ///
     /// Emits logs for debugging and errors.
-    pub fn auto_update(service: Self, exit: tokio::sync::oneshot::Receiver<()>) {
+    pub fn auto_update(service: Self, handle: environment::TaskExecutor) {
         let update_interval = Duration::from_millis(service.config().auto_update_interval_millis);
 
         let mut interval = interval_at(Instant::now(), update_interval);
@@ -303,9 +303,7 @@ impl Service {
             }
         };
 
-        let future = futures::future::select(Box::pin(update_future), exit);
-
-        tokio::task::spawn(future);
+        handle.spawn(update_future, "eth1");
     }
 
     async fn do_update(service: Self, update_interval: Duration) -> Result<(), ()> {