Skip tests requiring iptables.

Tests running `sudo` are problematic to run locally during development,
as you can't just run the tests - you need to watch them and wait for
sudo prompt. In this test, it would be better to use some kind of proxy.

As the test was already marked xfail, skip it to make development easier.

Author: Lorak-mmk

tests/integration/standard/test_shard_aware.py

@@ -26,6 +26,7 @@
     import unittest2 as unittest
 except ImportError:
     import unittest  # noqa
+import pytest
 
 from cassandra.cluster import Cluster
 from cassandra.policies import TokenAwarePolicy, RoundRobinPolicy, ConstantReconnectionPolicy
@@ -188,7 +189,7 @@ def test_closing_connections(self):
         time.sleep(10)
         self.query_data(self.session)
 
-    @unittest.expectedFailure
+    @pytest.mark.skip
     def test_blocking_connections(self):
         """
         Verify that reconnection is working as expected, when connection are being blocked.