Heat stack delete doesn't clean network policies for couple of stacks in scaled scenarios

[Vijay Anand]

Problem:
======
couple of network policies not removed for heat stack delete (35 stacks).

Test:
=====
35 SI/ stacks

Problem seen in race condition i.e. not consistently reproducible

Observation:
==========
1. heat stack delete for 35 stacks - cleaned up all stacks
2. related service instances are cleaned
3. Couple of network policies exists though the corresponding stacks are deleted

Complete Logs:
==============
GNAT PR 1141102 for Logs

snippet: After test complete
=======
root@csp-sol-mustang:~#
root@csp-sol-mustang:~# heat stack-list

root@csp-sol-mustang:~# nova list
+--------------------------------------+--------+--------+------------+-------------+--------------------------------+
| ID | Name | Status | Task State | Power State | Networks |
+--------------------------------------+--------+--------+------------+-------------+--------------------------------+
| 4f413ec4-a382-49fe-912f-980144c3f071 | vSPACE | ACTIVE | - | Running | Management Network=a.b.c.d |
+--------------------------------------+--------+--------+------------+-------------+--------------------------------+
root@csp-sol-mustang:~#
root@csp-sol-mustang:~#