tempest-RHOSP10-port create with non existent vn failed with wrong error message 'Server fault'

Tempest test case (https://github.com/openstack/tempest/blob/23aa354f178878ee4d5385db7ce51999726ef8b4/tempest/api/network/test_networks_negative.py) failed on RHOSP10 setup with an error "Server fault". Openstack expected error as per test case 'NotFound'

test case name: test_create_port_on_non_existent_network

./run_tempest.sh -N -d -C /etc/redhat-certification-openstack/tempest.conf --serial tempest.api.network.test_networks_negative.NetworksNegativeTestJSON.test_create_port_on_non_existent_network
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Traceback (most recent call last):
  File "tempest/api/network/test_networks_negative.py", line 82, in test_create_port_on_non_existent_network
    network_id=non_exist_net_id)
  File "/usr/lib/python2.7/site-packages/testtools/testcase.py", line 422, in assertRaises
    self.assertThat(our_callable, matcher)
  File "/usr/lib/python2.7/site-packages/testtools/testcase.py", line 433, in assertThat
    mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
  File "/usr/lib/python2.7/site-packages/testtools/testcase.py", line 483, in _matchHelper
    mismatch = matcher.match(matchee)
  File "/usr/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 108, in match
    mismatch = self.exception_matcher.match(exc_info)
  File "/usr/lib/python2.7/site-packages/testtools/matchers/_higherorder.py", line 62, in match
    mismatch = matcher.match(matchee)
  File "/usr/lib/python2.7/site-packages/testtools/testcase.py", line 414, in match
    reraise(*matchee)
  File "/usr/lib/python2.7/site-packages/testtools/matchers/_exception.py", line 101, in match
    result = matchee()
  File "/usr/lib/python2.7/site-packages/testtools/testcase.py", line 969, in __call__
    return self._callable_object(*self._args, **self._kwargs)
  File "tempest/lib/services/network/ports_client.py", line 29, in create_port
    return self.create_resource(uri, post_data)
  File "tempest/lib/services/network/base.py", line 60, in create_resource
    resp, body = self.post(req_uri, req_post_data)
  File "tempest/lib/common/rest_client.py", line 276, in post
    return self.request('POST', url, extra_headers, headers, body, chunked)
  File "tempest/lib/common/rest_client.py", line 664, in request
    self._error_checker(resp, resp_body)
  File "tempest/lib/common/rest_client.py", line 827, in _error_checker
    message=message)
tempest.lib.exceptions.ServerFault: Got server fault
Details: An unknown exception occurred.