$ git clone -n https://src.fedoraproject.org/rpms/plasma-systemmonitor.git /var/lib/mock/f42-build-side-1-3566295-46733/root/chroot_tmpdir/scmroot/plasma-systemmonitor
Cloning into '/var/lib/mock/f42-build-side-1-3566295-46733/root/chroot_tmpdir/scmroot/plasma-systemmonitor'...
$ git fetch origin 6b289b4d6969060475328fd8d47c8893b38e73ea:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-systemmonitor
 * [new ref]         6b289b4d6969060475328fd8d47c8893b38e73ea -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b289b4 6.4.0