Wait for interface to detach for required tests

This patchset waits for interfaces to detach during
test clean up in MiscPolicyActionsNetworkRbacTest test
class to avoid errors like [0], caused by data races
on server/network clean up.

[0] http://logs.openstack.org/27/570027/1/check/patrole-member/f4f69c3/job-output.txt.gz#_2018-05-22_20_13_22_117128

Depends-On: If23bd5947dea345b30a77bc83c5b3dbfa5a4267b
Change-Id: I7b1a095bb73f4814b756f9493f9e353a8f98e7da
diff --git a/patrole_tempest_plugin/tests/api/compute/test_server_misc_policy_actions_rbac.py b/patrole_tempest_plugin/tests/api/compute/test_server_misc_policy_actions_rbac.py
index d393a4c..63dee85 100644
--- a/patrole_tempest_plugin/tests/api/compute/test_server_misc_policy_actions_rbac.py
+++ b/patrole_tempest_plugin/tests/api/compute/test_server_misc_policy_actions_rbac.py
@@ -614,6 +614,9 @@
             self.interfaces_client, self.server['id'],
             interface['port_id'], 'ACTIVE')
         self.addCleanup(
+            waiters.wait_for_interface_detach, self.interfaces_client,
+            self.server['id'], interface['port_id'])
+        self.addCleanup(
             test_utils.call_and_ignore_notfound_exc,
             self.interfaces_client.delete_interface,
             self.server['id'], interface['port_id'])