$ git clone -n https://src.fedoraproject.org/rpms/CImg.git /var/lib/mock/f42-build-865013-172748/root/chroot_tmpdir/scmroot/CImg
Cloning into '/var/lib/mock/f42-build-865013-172748/root/chroot_tmpdir/scmroot/CImg'...
$ git fetch origin 9119023726188394431df46601c3a3803e781603:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/CImg
 * [new ref]         9119023726188394431df46601c3a3803e781603 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9119023 bump version