$ git clone -n https://src.fedoraproject.org/rpms/CImg.git /var/lib/mock/f39-build-1922131-42964/root/chroot_tmpdir/scmroot/CImg
Cloning into '/var/lib/mock/f39-build-1922131-42964/root/chroot_tmpdir/scmroot/CImg'...
$ git fetch origin d4b707ea12ee50bdbba9190f4dd8a9f4e30b00e6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/CImg
 * [new ref]         d4b707ea12ee50bdbba9190f4dd8a9f4e30b00e6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d4b707e Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild