$ git clone -n https://src.fedoraproject.org/rpms/rust-gix-shallow.git /var/lib/mock/f42-build-3262672-41241/root/chroot_tmpdir/scmroot/rust-gix-shallow
Cloning into '/var/lib/mock/f42-build-3262672-41241/root/chroot_tmpdir/scmroot/rust-gix-shallow'...
$ git fetch origin f99337f44999d7a7f376c9ed8302cc0eb572fdce:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gix-shallow
 * [new ref]         f99337f44999d7a7f376c9ed8302cc0eb572fdce -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f99337f Initial package (rhbz#2340272)