Update hacking for Python3

The repo is Python 3 now, so update hacking to version 3.0 which
supports Python 3.

Fix problems found by updated hacking version.

The tempest plugin is used on older branches as well.
We really only need hacking on master anyways,
where we no longer support python 2, so here we
make the requirement specific to python 3.

Change-Id: I885da1613e9cf754302700019a1207a279b3af2a
diff --git a/octavia_tempest_plugin/tests/test_base.py b/octavia_tempest_plugin/tests/test_base.py
index aab78c1..741bb1c 100644
--- a/octavia_tempest_plugin/tests/test_base.py
+++ b/octavia_tempest_plugin/tests/test_base.py
@@ -302,8 +302,8 @@
         network_kwargs = {
             'name': data_utils.rand_name("lb_member_vip_network")}
         if CONF.network_feature_enabled.port_security:
-                # Note: Allowed Address Pairs requires port security
-                network_kwargs['port_security_enabled'] = True
+            # Note: Allowed Address Pairs requires port security
+            network_kwargs['port_security_enabled'] = True
         result = cls.lb_mem_net_client.create_network(**network_kwargs)
         cls.lb_member_vip_net = result['network']
         LOG.info('lb_member_vip_net: {}'.format(cls.lb_member_vip_net))