Since upgrading from 17.10 to 18.04 I keep getting gnome-calendar popups asking me for my password to update "holidays in Austria" and "contacts" from Google Calendar. I have removed "holidays in Austria" from my Google Calendar, then reinstalled and removed it again but the popups keep on coming. I no longer need "holidays in Austria". I have both "Feiertage in Deutschland" and "Feiertage in Grossbritannien" in my Google Calendar and they sync with gnome-calendar without this popup appearing.
If anyone knows how to get rid of these annoying popups for a calendar I don't even use, I would be most grateful.