$ git clone -n https://src.fedoraproject.org/rpms/GMT.git /var/lib/mock/f42-build-863022-171338/root/chroot_tmpdir/scmroot/GMT
Cloning into '/var/lib/mock/f42-build-863022-171338/root/chroot_tmpdir/scmroot/GMT'...
$ git fetch origin ae12123d0c149b66702e5cf2d372c8e63595b0ff:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/GMT
 * [new ref]         ae12123d0c149b66702e5cf2d372c8e63595b0ff -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ae12123 Rebuild (GDAL)