Cancel periodic priority update on delete connection

Signed-off-by: Yannic Klem <yannic.klem@bosch.io>

connectivity/service/src/main/java/org/eclipse/ditto/connectivity/service/messaging/persistence/ConnectionPersistenceActor.java

@@ -638,6 +638,12 @@ protected Receive matchAnyWhenDeleted() {
                 .orElse(super.matchAnyWhenDeleted());
     }
 
+    @Override
+    protected void becomeDeletedHandler() {
+        this.cancelPeriodicPriorityUpdate();
+        super.becomeDeletedHandler();
+    }
+
     /**
      * Route search commands according to subscription ID prefix. This is necessary so that for connections with
      * client count > 1, all commands related to 1 search session are routed to the same client actor. This is achieved
@@ -857,6 +863,10 @@ private void startUpdatePriorityPeriodically(final Duration priorityUpdateInterv
                 priorityUpdateInterval);
     }
 
+    private void cancelPeriodicPriorityUpdate() {
+        timers().cancel(Control.TRIGGER_UPDATE_PRIORITY);
+    }
+
     private void respondWithEmptyLogs(final RetrieveConnectionLogs command, final ActorRef origin) {
         log.debug("ClientActor not started, responding with empty connection logs.");
         final RetrieveConnectionLogsResponse logsResponse = RetrieveConnectionLogsResponse.of(