$ git clone -n https://src.fedoraproject.org/rpms/rust-git-delta.git /var/lib/mock/f39-build-2341900-59796/root/chroot_tmpdir/scmroot/rust-git-delta
Cloning into '/var/lib/mock/f39-build-2341900-59796/root/chroot_tmpdir/scmroot/rust-git-delta'...
$ git fetch origin 35f81d615bf212d77875175a15ce31eeda1264e6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-git-delta
 * [new ref]         35f81d615bf212d77875175a15ce31eeda1264e6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 35f81d6 Rebuilt for vte 0.13