updateEvent changes only the event fields you provide. Use it to reschedule,
rename, recolor, or change guests without replacing unrelated event metadata.
Example
Inputs
event is required and accepts an event ID or Calendar event URL. calendar
defaults to "primary". Provide at least one mutable field: summary,
schedule, description, location, colorId, attendees, attachments,
recurrence, reminders, extendedProperties, transparency, visibility,
the three guestsCan... permissions, or createMeet: true. These fields use
the same types as Create event.
sendUpdates accepts "all", "externalOnly", or "none"; account
selects the Google account.
Arrays and objects supplied to a patch are provider replacements for those
fields. For example, attendees: [] removes the attendee list and
attachments: [] removes attachments.
Output
Returns the updatedCalendarEvent; see Get event. The action fails if the event is not in the selected calendar or the account cannot edit it.