fix: fetching calendar-links for seated events

[supalarry]

Problem

When booking a seated event and then trying to fetch its calendar links server errors with 500

Solution

First, we need to understand how do calendar links work for seated events - does every seat get the same calendar link? I (Lauris) asked that to Hariom and on Slack https://calendso.slack.com/archives/C08B8SYUY02/p1759401585274159

Second, the error happens somewhere in getCalendarLinks function in packages/features/bookings/lib/getCalendarLinks.ts that is called in apps/api/v2/src/ee/bookings/2024-08-13/services/bookings.service.ts.

[linear]

CAL-6503