fix: streamlined discount display in all breakdowns

tests/Controller/Booking/Edit/IndexControllerTest.php

@@ -25,6 +25,7 @@ use App\Service\BookingEditPreFlightChecker;
 use App\Service\BookingEditSubmitter;
 use App\Service\BookingSessionManager;
 use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
 use Symfony\Component\Form\FormInterface;
 use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpFoundation\Request;
@@ -816,6 +817,7 @@ final class TestableIndexController extends IndexController
             $editContextFactory,
             $preFlightChecker,
             $formSubmitter,
+            new NullLogger(),
         );
     }