Use unittest.mock instead of third party mock

Now that we no longer support py27, we can use the standard library
unittest.mock module instead of the third party mock lib.

Change-Id: I994c1f73ead8d3374b7bb67b557bec7535affc02
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>

ironic_inspector_client/test/functional.py

@@ -16,6 +16,7 @@ import os
 import sys
 import tempfile
 import unittest
+from unittest import mock
 
 import eventlet
 eventlet.monkey_patch()
@@ -24,7 +25,6 @@ from ironic_inspector import process
 from ironic_inspector.test import functional
 from keystoneauth1 import session as ks_session
 from keystoneauth1 import token_endpoint
-import mock
 from oslo_concurrency import processutils
 
 import ironic_inspector_client as client

ironic_inspector_client/test/test_common_http.py

@@ -13,10 +13,10 @@
 
 import json
 import unittest
+from unittest import mock
 
 from keystoneauth1 import exceptions
 from keystoneauth1 import session
-import mock
 
 from ironic_inspector_client.common import http
 

ironic_inspector_client/test/test_shell.py

@@ -15,8 +15,8 @@ import collections
 import io
 import sys
 import tempfile
+from unittest import mock
 
-import mock
 from osc_lib.tests import utils
 
 from ironic_inspector_client import shell

ironic_inspector_client/test/test_v1.py

@@ -13,10 +13,10 @@
 
 import collections
 import unittest
+from unittest import mock
 import uuid
 
 from keystoneauth1 import session
-import mock
 
 import ironic_inspector_client
 from ironic_inspector_client.common import http

lower-constraints.txt

@@ -28,7 +28,6 @@ jsonschema==2.6.0
 keystoneauth1==3.4.0
 linecache2==1.0.0
 mccabe==0.2.1
-mock==2.0.0
 monotonic==0.6
 msgpack-python==0.4.0
 munch==2.1.0
@@ -37,7 +36,7 @@ netifaces==0.10.4
 openstacksdk==0.11.2
 os-client-config==1.28.0
 os-service-types==1.2.0
-osc-lib==1.8.0
+osc-lib==2.1.0
 oslo.concurrency==3.25.0
 oslo.config==5.2.0
 oslo.i18n==3.15.3

test-requirements.txt

@@ -6,10 +6,9 @@ doc8>=0.6.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
 flake8-import-order>=0.17.1 # LGPLv3
 hacking>=3.0.0,<3.1.0 # Apache-2.0
-mock>=2.0.0 # BSD
 requests-mock>=1.2.0 # Apache-2.0
 oslo.concurrency>=3.25.0 # Apache-2.0
-osc-lib>=1.8.0 # Apache-2.0
+osc-lib>=2.1.0 # Apache-2.0
 python-openstackclient>=3.12.0 # Apache-2.0
 # Required for syntax highlighting check
 Pygments>=2.2.0 # BSD