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: Ia50cc4538bf4e148f3870dafb414109d4ca9ccc1

doc/requirements.txt

@@ -7,7 +7,6 @@
 # be installed in a specific order.
 #
 # Requirements for docs
-mock>=2.0.0 # BSD
 openstackdocstheme>=2.2.1 # Apache-2.0
 reno>=3.1.0 # Apache-2.0
 sphinx>=2.0.0,!=2.1.0 # BSD

lower-constraints.txt

@@ -41,7 +41,6 @@ keystoneauth1==3.4.0
 linecache2==1.0.0
 MarkupSafe==1.0
 mccabe==0.2.1
-mock==2.0.0
 monotonic==1.4
 msgpack==0.5.6
 munch==2.2.0

test-requirements.txt

@@ -10,5 +10,4 @@
 hacking>=1.1.0,<1.2.0 # Apache-2.0
 #
 coverage!=4.4,>=4.0 # Apache-2.0
-mock>=2.0.0 # BSD
 testtools>=2.2.0 # MIT

zaqar_ui/test/api_tests/test_rest_api.py

@@ -10,7 +10,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+from unittest import mock
 
 from openstack_dashboard.test import helpers as test
 from openstack_dashboard.test.test_data import utils

zaqar_ui/test/helpers.py

@@ -10,7 +10,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import mock
+from unittest import mock
 
 from openstack_dashboard.test import helpers
 from zaqarclient.queues.v2 import client as zaqar_client