Remove unused import for six in ipaddr filter (#67595)

This was caught in our ansible.netcommon collection testing.

Signed-off-by: Paul Belanger <pabelanger@redhat.com>

lib/ansible/plugins/filter/ipaddr.py

@@ -21,7 +21,6 @@ __metaclass__ = type
 
 from functools import partial
 import types
-from ansible.module_utils import six
 
 try:
     import netaddr