$ git clone -n https://src.fedoraproject.org/rpms/rpm-git-tag-sort.git /var/lib/mock/f41-build-side-1-2849121-33909/root/chroot_tmpdir/scmroot/rpm-git-tag-sort
Cloning into '/var/lib/mock/f41-build-side-1-2849121-33909/root/chroot_tmpdir/scmroot/rpm-git-tag-sort'...
$ git fetch origin a7e0b753be699f50c3377bb287fbe87e4f700aa7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rpm-git-tag-sort
 * [new ref]         a7e0b753be699f50c3377bb287fbe87e4f700aa7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a7e0b75 Rebuild for libgit2 1.8.x