Use unittest.mock instead of mock

The mock third party library was needed for mock support in py2
runtimes. Since we now only support py36 and later, we can use the
standard lib unittest.mock module instead.

Change-Id: If7d7ed6f3b398b48ace903f8307adc64264b2f1b

doc/requirements.txt

@@ -1 +0,0 @@
-../test-requirements.txt

doc/requirements.txt

@@ -0,0 +1,13 @@
+netaddr # BSD
+stestr>=2.0.0 # Apache-2.0
+oslotest>=3.2.0 # Apache-2.0
+ruamel.yaml
+pre-commit # MIT
+ansible>=2.8
+
+# this is required for the docs build jobs
+sphinx>=2.0.0,!=2.1.0 # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
+reno>=3.1.0 # Apache-2.0
+doc8>=0.8.0 # Apache-2.0
+bashate>=0.6.0 # Apache-2.0

test-requirements.txt

@@ -1,5 +1,4 @@
 netaddr # BSD
-mock>=2.0.0 # BSD
 stestr>=2.0.0 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
 ruamel.yaml

tests/plugins/action/test_timestamp_file.py

@@ -13,7 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from unittest import mock
 
 from ansible.errors import AnsibleActionFail
 from ansible.errors import AnsibleActionSkip

tests/plugins/modules/test_tripleo_shell_script.py

@@ -13,7 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import mock
+from unittest import mock
 
 from plugins.modules import tripleo_shell_script
 from tests import base as tests_base