add missing use

DependencyInjection/ABELkeycloakBearerOnlyAdapterExtension.php

@@ -6,6 +6,7 @@ namespace ABEL\Bundle\keycloakBearerOnlyAdapterBundle\DependencyInjection;
 use Symfony\Component\Config\FileLocator;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Extension\Extension;
+use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
 
 class ABELkeycloakBearerOnlyAdapterExtension extends Extension
 {