Open gnome-maps (or other map application) when clicking on a map icon next to the location address. Resolves: https://gitlab.gnome.org/GNOME/gnome-calendar/-/issues/326 Signed-off-by: Alistair Francis <alistair@alistair23.me> Part-of: <https://gitlab.gnome.org/GNOME/gnome-calendar/-/merge_requests/590>