Fixing PHPStan on generated DaoFactory

Author: moufmouf

src/Utils/TDBMDaoGenerator.php

@@ -330,7 +330,7 @@ public function __construct(ContainerInterface \$container)
             $daoInstanceName = self::toVariableName($daoClassName);
 
             $str .= '    /**
-     * @var '.$daoClassName.'
+     * @var '.$daoClassName.'|null
      */
     private $'.$daoInstanceName.';