$ git clone -n https://src.fedoraproject.org/rpms/rust-uu_runcon.git /var/lib/mock/f41-build-3152103-40629/root/chroot_tmpdir/scmroot/rust-uu_runcon
Cloning into '/var/lib/mock/f41-build-3152103-40629/root/chroot_tmpdir/scmroot/rust-uu_runcon'...
$ git fetch origin 4b476e54b2d89fbeccaa7167e2a92bf6d3e578df:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-uu_runcon
 * [new ref]         4b476e54b2d89fbeccaa7167e2a92bf6d3e578df -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4b476e5 Initial package; Fixes: RHBZ#2308425