$ git clone -n https://src.fedoraproject.org/rpms/plasma-disks.git /var/lib/mock/f42-build-side-1-3578389-46814/root/chroot_tmpdir/scmroot/plasma-disks
Cloning into '/var/lib/mock/f42-build-side-1-3578389-46814/root/chroot_tmpdir/scmroot/plasma-disks'...
$ git fetch origin 9b9825fba81922cbdadd7c5021d89d1303d5fb18:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-disks
 * [new ref]         9b9825fba81922cbdadd7c5021d89d1303d5fb18 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9b9825f 6.4.1