feat: auto-booking services

addresses #869cfcptv

tests/Form/Service/ParticipantFieldOptionsProviderMandatoryServiceTest.php

@@ -91,6 +91,7 @@ class ParticipantFieldOptionsProviderMandatoryServiceTest extends TestCase
         $nonMandatoryService->available = 10;
         $nonMandatoryService->price = 10.0;
         $nonMandatoryService->mandatory = false;
+        $nonMandatoryService->autoBook = true;
 
         $travel = $this->createTravelWithAdditionalServices([$nonMandatoryService]);
         $bookingDto = new BookingDto($travel, 1);