fix: exclude cancelled participants' services from price breakdown

src/Service/BookingConfigurator.php

@@ -288,7 +288,8 @@ class BookingConfigurator
         int $participantIndex,
         ParticipantDto $participant,
     ): bool {
-        if (null === $participant->dateOfBirth) {
+        // A cancelled participant's services are no longer billed, so nothing may be added for them
+        if (true === $participant->isCanceled() || null === $participant->dateOfBirth) {
             return false;
         }