update version of freeradius-client in hammer.py
freeradius-client has been updated due to issue: https://gitlab.isc.org/isc-projects/kea/issues/1140 Now hammer.py needs to change to updated version of freeradius-client.
freeradius-client has been updated due to issue: https://gitlab.isc.org/isc-projects/kea/issues/1140 Now hammer.py needs to change to updated version of freeradius-client.