Restart of outbound stream if upstream completed (unexpectedly), #31081

* In the logs attached to the issue we can see that an outbound connection is not
  re-established after "Upstream finished" (broken pipe).
* Normally that is handled by the inner RestartFlow around the connection flow, but
  if that has reached it's maxRestarts (3) it will complete the entire stream and
  attachOutboundStreamRestart would not handle that as a restart case.

akka-remote/src/main/scala/akka/remote/artery/Association.scala

@@ -958,9 +958,14 @@ private[remote] class Association(
 
     implicit val ec = materializer.executionContext
     streamCompleted.foreach { _ =>
-      // shutdown as expected
-      // countDown the latch in case threads are waiting on the latch in outboundControlIngress method
-      materializing.countDown()
+      if (transport.isShutdown || isRemovedAfterQuarantined()) {
+        // shutdown as expected
+        // countDown the latch in case threads are waiting on the latch in outboundControlIngress method
+        materializing.countDown()
+      } else {
+        log.debug("{} to [{}] was completed. It will be restarted if used again.", streamName, remoteAddress)
+        lazyRestart()
+      }
     }
     streamCompleted.failed.foreach {
       case ArteryTransport.ShutdownSignal =>
@@ -1034,7 +1039,7 @@ private[remote] class Association(
         } else {
           log.error(
             cause,
-            s"{} to [{}] failed and restarted {} times within {} seconds. Terminating system. ${cause.getMessage}",
+            s"{} to [{}] failed and restarted {} times within {} seconds. Terminating system. ${cause.getMessage}",
             streamName,
             remoteAddress,
             advancedSettings.OutboundMaxRestarts,