$ git clone -n https://src.fedoraproject.org/rpms/memtest86+.git /var/lib/mock/f40-build-763399-122479/root/chroot_tmpdir/scmroot/memtest86+
Cloning into '/var/lib/mock/f40-build-763399-122479/root/chroot_tmpdir/scmroot/memtest86+'...
$ git fetch origin b65d1cd8a1c23da3c091585c75d0aad3f6d3cb09:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/memtest86+
 * [new ref]         b65d1cd8a1c23da3c091585c75d0aad3f6d3cb09 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b65d1cd Update kernel-install Plugin