$ git clone -n https://src.fedoraproject.org/rpms/reposurgeon.git /var/lib/mock/f39-build-1929401-43080/root/chroot_tmpdir/scmroot/reposurgeon
Cloning into '/var/lib/mock/f39-build-1929401-43080/root/chroot_tmpdir/scmroot/reposurgeon'...
$ git fetch origin f99ce88b3cec3711cf0a120cf1f81cbad22260ea:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/reposurgeon
 * [new ref]         f99ce88b3cec3711cf0a120cf1f81cbad22260ea -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f99ce88 reposurgeon: 4.38 release