$ git clone -n https://src.fedoraproject.org/rpms/Add64.git /var/lib/mock/f41-build-side-1-2630193-25598/root/chroot_tmpdir/scmroot/Add64
Cloning into '/var/lib/mock/f41-build-side-1-2630193-25598/root/chroot_tmpdir/scmroot/Add64'...
$ git fetch origin 5ddc9815ed1a6be43050aa5025d0059d6456ff0c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/Add64
 * [new ref]         5ddc9815ed1a6be43050aa5025d0059d6456ff0c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5ddc981 convert GPLv3 license to SPDX