$ git clone -n https://src.fedoraproject.org/rpms/python-mdx_gh_links.git /var/lib/mock/f40-build-2222779-52711/root/chroot_tmpdir/scmroot/python-mdx_gh_links
Cloning into '/var/lib/mock/f40-build-2222779-52711/root/chroot_tmpdir/scmroot/python-mdx_gh_links'...
$ git fetch origin 154c486b776c5a566cd3294fc12622c7a645a1b0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-mdx_gh_links
 * [new ref]         154c486b776c5a566cd3294fc12622c7a645a1b0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 154c486 Update to 0.4