$ git clone -n https://src.fedoraproject.org/rpms/libs3.git /var/lib/mock/f40-build-2008309-45362/root/chroot_tmpdir/scmroot/libs3
Cloning into '/var/lib/mock/f40-build-2008309-45362/root/chroot_tmpdir/scmroot/libs3'...
$ git fetch origin cff603d1ca405ad3cfa7443546fa7049046aadb8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libs3
 * [new ref]         cff603d1ca405ad3cfa7443546fa7049046aadb8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cff603d Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild