Try to fix the continuous build
Try to fix the continuous build

We are using to-pixdata processing for some of the resources
in tests/, but gdk-pixbuf-pixdata has not been installed on
the system yet. So pass the location of the just-built one
via the GDK_PIXBUF_PIXDATA env var.

YueLinHo/MB3Gdk-pixbuf,Distrotech/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,Distrotech/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,GNOME/gdk-pixbuf,Distrotech/gdk-pixbuf,Distrotech/gdk-pixbuf,GNOME/gdk-pixbuf,GNOME/gdk-pixbuf,GNOME/gdk-pixbuf,Distrotech/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf