Disable collection fetch for the findBy() paginator

This change is related to the changes introduced by this PR:
javiereguiluz@d171056

Controller/AdminController.php

@@ -395,7 +395,7 @@ protected function findBy($entityClass, $searchQuery, array $searchableFields, $
             $query->orWhere("entity.$name LIKE :query")->setParameter('query', '%'.$searchQuery.'%');
         }
 
-        $paginator = new Pagerfanta(new DoctrineORMAdapter($query));
+        $paginator = new Pagerfanta(new DoctrineORMAdapter($query, false));
         $paginator->setMaxPerPage($maxPerPage);
         $paginator->setCurrentPage($page);