[gi] use correct format stings when setting errors
[gi] use correct format stings when setting errors

thiblahute/pygobject,jdahlin/pygobject,choeger/pygobject-cmake,MathieuDuponchelle/pygobject,pexip/pygobject,GNOME/pygobject,davibe/pygobject,sfeltman/pygobject,choeger/pygobject-cmake,choeger/pygobject-cmake,davibe/pygobject,jdahlin/pygobject,davibe/pygobject,GNOME/pygobject,thiblahute/pygobject,pexip/pygobject,jdahlin/pygobject,MathieuDuponchelle/pygobject,sfeltman/pygobject,MathieuDuponchelle/pygobject,thiblahute/pygobject,davidmalcolm/pygobject,davidmalcolm/pygobject,davidmalcolm/pygobject,GNOME/pygobject,davibe/pygobject,pexip/pygobject,sfeltman/pygobject