$ git clone -n https://src.fedoraproject.org/rpms/mlpack.git /var/lib/mock/f39-build-1927890-43062/root/chroot_tmpdir/scmroot/mlpack
Cloning into '/var/lib/mock/f39-build-1927890-43062/root/chroot_tmpdir/scmroot/mlpack'...
$ git fetch origin cadf5b70b424c9a64be7bf228adb692f0d1fe30b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mlpack
 * [new ref]         cadf5b70b424c9a64be7bf228adb692f0d1fe30b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cadf5b7 Merge branch 'rawhide' into f39