$ git clone -n https://src.fedoraproject.org/rpms/ksystemstats.git /var/lib/mock/f42-build-side-1-3575210-46778/root/chroot_tmpdir/scmroot/ksystemstats
Cloning into '/var/lib/mock/f42-build-side-1-3575210-46778/root/chroot_tmpdir/scmroot/ksystemstats'...
$ git fetch origin 42094ee3e775b00413b5b42e78988f57845c2a20:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ksystemstats
 * [new ref]         42094ee3e775b00413b5b42e78988f57845c2a20 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 42094ee 6.4.0