Before this commit, the permission defined in Google Calendar of editing events by guests was always set in Odoo Calendar as 'True', even though there was also the 'False' option. This way, creating an event that didn't accept being edited by guests in Google and then updating it in Odoo by a guest was creating duplicates in Odoo Calendar and wrong lists of attendees.
After this commit, the permission of guests modifying the event is taken into account in Odoo Calendar. If a guest updates an event that doesn't allow updates, a warning is shown forbidding the update and the reason explained.
closesodoo/odoo#127397
Task-id: 3276829
Signed-off-by: Arnaud Joset (arj) <arj@odoo.com>