fix: 'Invalid event length' error for 1 hour dynamic events (#13522)

* fix #13507 'Invalid event length' when creating dynamic events with a 1 hour duration

* Fix failing e2e tests by dynamically injecting lengths for dynamic events

--amend 1: misc indentation cleanup
--amend 2: Added condition to only update event metadata when slug is dynamic and multipleDuration is empty

* Override the multipleDuration property while constructing the dynamicEvent object itself

---------

Co-authored-by: Keith Williams <keithwillcode@gmail.com>
Co-authored-by: Carina Wollendorfer <30310907+CarinaWolli@users.noreply.github.com>

packages/lib/defaultEvents.ts

@@ -112,6 +112,7 @@ const dynamicEvent = {
   descriptionAsSafeHTML: "",
   position: 0,
   ...commons,
+  metadata: EventTypeMetaDataSchema.parse({ multipleDuration: [15, 30, 60, 90] }),
 };
 
 const defaultEvents = [dynamicEvent];