test: remove dep on mock, use unittest.mock instead

Signed-off-by: Dan Streetman <ddstreet@canonical.com>

debian/control

@@ -23,7 +23,6 @@ Build-Depends:
  python3-flake8,
  python3-httplib2,
  python3-launchpadlib,
- python3-mock,
  python3-requests <!nocheck>,
  python3-setuptools,
  python3-termcolor <!nocheck>,

test-requirements.txt

@@ -1,4 +1,3 @@
 coverage
 flake8 >= 3.8.0
 nose
-mock

ubuntutools/test/test_archive.py

@@ -15,11 +15,11 @@
 # PERFORMANCE OF THIS SOFTWARE.
 
 
-import mock
 import os.path
 import shutil
 import tempfile
 from io import BytesIO
+from unittest import mock
 
 import ubuntutools.archive
 from ubuntutools.test import unittest

ubuntutools/test/test_config.py

@@ -16,10 +16,10 @@
 # PERFORMANCE OF THIS SOFTWARE.
 
 import locale
-import mock
 import os
 # import sys
 from io import StringIO
+from unittest import mock
 
 from ubuntutools.config import UDTConfig, ubu_email
 from ubuntutools.test import unittest

ubuntutools/test/test_update_maintainer.py

@@ -16,10 +16,10 @@
 
 """Test suite for ubuntutools.update_maintainer"""
 
-import mock
 import os
 # import sys
 from io import StringIO
+from unittest import mock
 
 from ubuntutools.test import unittest
 from ubuntutools.update_maintainer import update_maintainer