unittest: use unittest.mock instead of mock

because the absence of unittest.mock on python2.7, we still fallback to
mock

tests/test_plugins/test_kiwi_builder.py

@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 import tempfile
 import unittest
 

tests/test_plugins/test_kiwi_cli.py

@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 import io
 import os
 import sys

tests/test_plugins/test_kiwi_hub.py

@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 import unittest
 
 import koji

tests/test_plugins/test_protonmsg.py

@@ -6,9 +6,13 @@ import unittest
 import pytest
 
 import protonmsg
-import mock
+try:
+    from unittest import mock
+    from unittest.mock import patch, MagicMock
+except ImportError:
+    import mock
+    from mock import patch, MagicMock
 import six
-from mock import patch, MagicMock
 if six.PY2:
     from ConfigParser import SafeConfigParser as ConfigParser
 else:

tests/test_plugins/test_runroot_builder.py

@@ -1,6 +1,9 @@
 from __future__ import absolute_import
 import copy
-import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 import unittest
 
 import six.moves.configparser

tests/test_plugins/test_runroot_cli.py

@@ -1,6 +1,9 @@
 from __future__ import absolute_import
 import io
-import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 import six
 import unittest
 import os

tests/test_plugins/test_runroot_hub.py

@@ -1,5 +1,5 @@
 from __future__ import absolute_import
-import mock
+from unittest import mock
 import unittest
 
 import koji

tests/test_plugins/test_save_failed_tree_builder.py

@@ -1,5 +1,8 @@
 from __future__ import absolute_import
-import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 import os
 import sys
 import unittest

tests/test_plugins/test_save_failed_tree_cli.py

@@ -1,5 +1,8 @@
 from __future__ import absolute_import
-import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 import six
 import unittest
 

tests/test_plugins/test_sidetag_cli.py

@@ -1,6 +1,9 @@
 from __future__ import absolute_import
 import io
-import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock
 import six
 import unittest
 import os

tests/test_plugins/test_sidetag_hub.py

@@ -1,5 +1,5 @@
 from __future__ import absolute_import
-import mock
+from unittest import mock
 import unittest
 
 import koji