DependencyNode: Use static call to avoid unnecessary columns in case of summary query

Author: sukhwinder33445

library/Icingadb/Model/DependencyNode.php

@@ -170,7 +170,7 @@ public static function forHost(string $hostId, Connection $db, bool $fetchParent
                 ->getTarget()
         );
 
-        $query = self::on($db);
+        $query = static::on($db);
 
         $query->filter(new Exists(
             $edge->assembleSelect()