Use unittest.mock instead of PyPI mock

Now that py2 is gone, oslotest dropped dependency on mock and will
soon affect Ussuri CI [1], let's use unittest.mock built in py3.

This also fixes py38 jobs and proactively prevents py36 and py37
failing due to [1]. This is because we never included mock in
test-requirements (but in lower-constraints where it does not
really belong at all) and instead relied on oslotest to bring
it in.

[1] https://review.opendev.org/716322

Change-Id: Iceedcc7ad0d087414f6f94dfc0235fda4754be63

2 files changed, 2 insertions, 2 deletions

diff --git a/kolla/tests/base.py b/kolla/tests/base.py
index 1c43b7619..94bdba509 100644
--- a/kolla/tests/base.py
+++ b/kolla/tests/base.py
@@ -11,9 +11,9 @@
 # limitations under the License.
 
 import os
+from unittest import mock
 
 import fixtures
-import mock
 from oslo_config import cfg
 from oslotest import base as oslotest_base
 
diff --git a/kolla/tests/test_build.py b/kolla/tests/test_build.py
index 5b3e981d6..b7f5c30c0 100644
--- a/kolla/tests/test_build.py
+++ b/kolla/tests/test_build.py
@@ -12,10 +12,10 @@
 
 import fixtures
 import itertools
-import mock
 import os
 import requests
 import sys
+from unittest import mock
 
 from kolla.cmd import build as build_cmd
 from kolla import exception