Setting up openstack tests for iptables formula

Change-Id: Ib924de131cca35052b50555c280484ef0161ebaa
diff --git a/tests/pillar/iptables.sls b/tests/pillar/iptables.sls
index 05fe015..ef797c6 100644
--- a/tests/pillar/iptables.sls
+++ b/tests/pillar/iptables.sls
@@ -44,8 +44,8 @@
                 action: LOG
       nat:
         chains:
-          OUTPUT:
-          PREROUTING:
+          OUTPUT: {}
+          PREROUTING: {}
           POSTROUTING:
             policy: ACCEPT
             ruleset: