$ git clone -n https://src.fedoraproject.org/rpms/bomber.git /var/lib/mock/f42-build-3426385-45168/root/chroot_tmpdir/scmroot/bomber
Cloning into '/var/lib/mock/f42-build-3426385-45168/root/chroot_tmpdir/scmroot/bomber'...
$ git fetch origin ce05623d24a7a4b6751d0029e12e27d5c3ff9761:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bomber
 * [new ref]         ce05623d24a7a4b6751d0029e12e27d5c3ff9761 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ce05623 24.12.3