Merge pull request #11967 from LK4D4/fix_panic

Avoid ServeApi race condition

api/server/server_linux.go

@@ -82,7 +82,9 @@ func AcceptConnections(job *engine.Job) error {
 	// Tell the init daemon we are accepting requests
 	go systemd.SdNotify("READY=1")
 	// close the lock so the listeners start accepting connections
-	if activationLock != nil {
+	select {
+	case <-activationLock:
+	default:
 		close(activationLock)
 	}
 	return nil