fix: initialize DOI in booking create flow with newsletter subscription

src/Controller/Booking/Create/Step4Controller.php

@@ -112,7 +112,7 @@ class Step4Controller extends AbstractBookingCreateController
                 if (true === $newsletterOptInSelected) {
                     try {
                         $targetParticipant = $this->resolveNewsletterTargetParticipant($bookingCreateDto);
-                        $this->doubleOptInService->requestDefaultListSubscription(
+                        $this->doubleOptInService->requestConfirmation(
                             $newsletterTargetEmail,
                             $targetParticipant?->firstName,
                             $targetParticipant?->lastName,