migrate from external mock package to stdlib unittest.mock (#1673)

It was moved to the stdlib in python 3.3, and the PyPI version is a
backport for python versions less than 3.3.

CHANGES.rst

@@ -42,6 +42,7 @@ fixes:
 - docs: add readthedocs yaml config (#1661)
 - fix: broken integration tests (#1668)
 - style: replace format() with f-strings (#1667)
+- migrate from external mock package to stdlib unittest.mock (#1673)
 
 
 v6.1.9 (2022-06-11)

tests/cascade_dependencies_test.py

@@ -1,7 +1,7 @@
 import os
 import pathlib
 
-import mock
+from unittest import mock
 import pytest
 
 extra_plugin_dir = os.path.join(

tests/commands_test.py

@@ -9,7 +9,7 @@
 from tempfile import mkdtemp
 
 import pytest
-from mock import MagicMock
+from unittest.mock import MagicMock
 
 extra_plugin_dir = path.join(path.dirname(path.realpath(__file__)), "dummy_plugin")
 

tox.ini

@@ -4,7 +4,6 @@ skip_missing_interpreters = True
 
 [testenv]
 deps =
-    mock
     pytest
     slackclient>=1.0.5,<2.0