$ git clone -n https://src.fedoraproject.org/rpms/gdk-pixbuf2-modules-extra.git /var/lib/mock/f41-build-835874-158748/root/chroot_tmpdir/scmroot/gdk-pixbuf2-modules-extra
Cloning into '/var/lib/mock/f41-build-835874-158748/root/chroot_tmpdir/scmroot/gdk-pixbuf2-modules-extra'...
$ git fetch origin 4988717ef80aece68f49f5c8bad4dae24e4d4a36:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gdk-pixbuf2-modules-extra
 * [new ref]         4988717ef80aece68f49f5c8bad4dae24e4d4a36 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4988717 Drop README