[framework] fixed query wrongly loading flags from Product instead of…

… ProductDomain (#3310)

Co-authored-by: Milan Staňo <milan.stano@shopsys.com>

src/Model/Product/Filter/FlagFilterChoiceRepository.php

@@ -104,7 +104,7 @@ protected function getVisibleFlagsByProductsQueryBuilder(QueryBuilder $productsQ
 
         $clonedProductsQueryBuilder
             ->select('1')
-            ->join('p.flags', 'pf')
+            ->join('pd.flags', 'pf')
             ->andWhere('pf.id = f.id')
             ->andWhere('f.visible = true')
             ->resetDQLPart('orderBy');