Retry a booking’s calendar event

Tries again to put a booking you host (or any in a team you administer) in its organizer's booking calendar: creates the event if it isn't there, else updates it to the booking's time and asks the calendar again for a missing Google Meet or Teams link. For a cancelled booking, deletes the event. Use it on a booking with a calendarProblem (from list_bookings or get_host_booking). Returns the booking: calendarProblem is gone when it worked. When it says the calendar can't be reached, the organizer must reconnect it in the Tempi web app under Calendars first. 409 not_confirmed for requests and unpaid bookings, which go on the calendar later.