Description of problem:
Tempest cleanup utility does not always delete and destroy used OpenStack resources.

**Reproduce Steps:
$ tempest cleanup --init-saved-state
$ execute selected manila upstream api tests
$ tempest cleanup

**User impact: Tests may fail due to insufficient resources.

**Failure example:
setUpClass (manila_tempest_tests.tests.api.admin.test_user_messages.UserMessageTest)
------------------------------------------------------------------------------------
Captured traceback:
~~~~~~~~~~~~~~~~~~~
    b'Traceback (most recent call last):'
    b' File "/usr/lib/python3.6/site-packages/tempest/test.py", line 173, in setUpClass'
    b' six.reraise(etype, value, trace)'
    b' File "/usr/lib/python3.6/site-packages/six.py", line 675, in reraise'
    b' raise value'
    b' File "/usr/lib/python3.6/site-packages/tempest/test.py", line 158, in setUpClass'
    b' cls.setup_credentials()'
    b' File "/usr/lib/python3.6/site-packages/tempest/test.py", line 377, in setup_credentials'
    b' credential_type=credentials_type)'
    b' File "/usr/lib/python3.6/site-packages/tempest/test.py", line 682, in get_client_manager'
    b' creds = getattr(cred_provider, credentials_method)()'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/dynamic_creds.py", line 356, in get_admin_creds'
    b" return self.get_credentials('admin')"
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/dynamic_creds.py", line 345, in get_credentials'
    b' credentials.tenant_id)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/dynamic_creds.py", line 262, in _create_network_resources'
    b' router = self._create_router(router_name, tenant_id)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/dynamic_creds.py", line 323, in _create_router'
    b' resp_body = self.routers_admin_client.create_router(**kwargs)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/services/network/routers_client.py", line 27, in create_router'
    b' return self.create_resource(uri, post_body)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/services/network/base.py", line 61, in create_resource'
    b' resp, body = self.post(req_uri, req_post_data)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 283, in post'
    b" return self.request('POST', url, extra_headers, headers, body, chunked)"
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 679, in request'
    b' self._error_checker(resp, resp_body)'
    b' File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 800, in _error_checker'
    b' raise exceptions.Conflict(resp_body, resp=resp)'
    b'tempest.lib.exceptions.Conflict: Conflict with state of target resource'
    b"Details: {'type': 'IpAddressGenerationFailure', 'message': 'No more IP addresses available on network 166b710f-cb4a-4eaa-af74-269964078dbe.', 'detail': ''}"
    b''


**Screen captures:
(overcloud) [stack@undercloud-0 testing_dir]$ ll saved_state.json
-rw-rw-r--. 1 stack stack 2675 May 23 17:56 saved_state.json

(overcloud) [stack@undercloud-0 testing_dir]$ openstack network list
+--------------------------------------+------------------------------------------+--------------------------------------+
| ID | Name | Subnets |
+--------------------------------------+------------------------------------------+--------------------------------------+
| 03e522a1-c3bd-421f-84ce-30bbf164dbd9 | tempest-share-service-1723054483-network | a0b7670c-b605-4504-9b4a-7e7f1af2032e |
| 0b53019a-0bcd-4351-8df0-6eb0fed3793e | tempest-share-service-1820279606-network | c63bf07c-8a27-4516-aa07-da24377912cd |
| 0fab7ada-920f-4847-87bf-40fd7b2d7882 | tempest-share-service-1322603070-network | a2529d4f-c6f1-46af-b73c-39d9d6dfd971 |
| 110d202f-e49a-4a81-87a8-92e88698c75e | tempest-share-service-1051501383-network | ebcf2d0f-30c4-4a84-8463-dace40089e20 |
| 166b710f-cb4a-4eaa-af74-269964078dbe | public | d4e8879e-a11e-4a42-83b3-1fdccad633ae |
| 249d773b-f555-492d-a88c-8b59a5db0ac5 | tempest-share-service-1237827927-network | d40f3765-5fdd-4313-b991-0a9fbfdba00b |
...

(overcloud) [stack@undercloud-0 testing_dir]$ tempest cleanup
Begin cleanup
Process 0 projects

(overcloud) [stack@undercloud-0 testing_dir]$ openstack network list
+--------------------------------------+------------------------------------------+--------------------------------------+
| ID | Name | Subnets |
+--------------------------------------+------------------------------------------+--------------------------------------+
| 03e522a1-c3bd-421f-84ce-30bbf164dbd9 | tempest-share-service-1723054483-network | a0b7670c-b605-4504-9b4a-7e7f1af2032e |
| 0b53019a-0bcd-4351-8df0-6eb0fed3793e | tempest-share-service-1820279606-network | c63bf07c-8a27-4516-aa07-da24377912cd |
| 0fab7ada-920f-4847-87bf-40fd7b2d7882 | tempest-share-service-1322603070-network | a2529d4f-c6f1-46af-b73c-39d9d6dfd971 |
| 110d202f-e49a-4a81-87a8-92e88698c75e | tempest-share-service-1051501383-network | ebcf2d0f-30c4-4a84-8463-dace40089e20 |
| 166b710f-cb4a-4eaa-af74-269964078dbe | public | d4e8879e-a11e-4a42-83b3-1fdccad633ae |
| 249d773b-f555-492d-a88c-8b59a5db0ac5 | tempest-share-service-1237827927-network | d40f3765-5fdd-4313-b991-0a9fbfdba00b |
...

Version-Release number of selected component (if applicable):
The current version for rhos-15: openstack-tempest-21.0.0-0.20191209200452.702b21c.el8ost.noarch.rpm

Additional info:
If a resource is associated with a project which has been already removed and the resource is from project services category, it won't be cleaned.
However, some service resources can be deleted all at once without iteration over the projects.
More info in the attached Launchpad bug