Trove mysql instance created by heat template don't show the Security group association

[Ranjitha Vemula]

When a mysql instance created with heat template, trove secgroup-show <instance id> errors out.

ERROR: SecurityGroupInstanceAssociation Not Found

Ran integration test on devstack for --group=blackbox noticed the error, below is the trace

======================================================================
ERROR: proboscis.case.MethodTest (setUp)
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Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/proboscis/case.py", line 296, in testng_method_mistake_capture_func
    compatability.capture_type_error(s_func)
  File "/usr/local/lib/python2.7/dist-packages/proboscis/compatability/exceptions_2_6.py", line 27, in capture_type_error
    func()
  File "/usr/local/lib/python2.7/dist-packages/proboscis/case.py", line 350, in func
    func(test_case.state.get_state())
  File "/opt/stack/trove/trove/tests/api/instances.py", line 776, in setUp
    instance_info.id)
  File "/opt/stack/python-troveclient/troveclient/v1/security_groups.py", line 52, in get
    "security_group")
  File "/opt/stack/python-troveclient/troveclient/base.py", line 162, in _get
    resp, body = self.api.client.get(url)
  File "/opt/stack/python-troveclient/troveclient/compat/client.py", line 237, in get
    return self._cs_request(url, 'GET', **kwargs)
  File "/opt/stack/python-troveclient/troveclient/compat/client.py", line 231, in _cs_request
    return request()
  File "/opt/stack/python-troveclient/troveclient/compat/client.py", line 221, in request
    **kwargs)
  File "/opt/stack/python-troveclient/troveclient/compat/client.py", line 209, in _time_request
    resp, body = self.request(url, method, **kwargs)
  File "/opt/stack/python-troveclient/troveclient/compat/client.py", line 187, in request
    raise exceptions.from_response(resp, body)
NotFound: Not found (HTTP SecurityGroupInstanceAssociation Not Found (HTTP 404)
-------------------- >> begin captured logging << --------------------