Remove six from test codes

This removes six from some of the tests code. The other test codes will
be updated in per-driver changes.

Change-Id: Ib168d5831ce30793b22a33aec85b81103a4150a7

cinder/tests/stubs/oslo_i18n/_message.pyi

@@ -2,13 +2,12 @@
 #
 # NOTE: This dynamically typed stub was automatically generated by stubgen.
 
-import six
 from typing import Any, Optional
 
 CONTEXT_SEPARATOR: str
 LOG: Any
 
-class Message(six.text_type):
+class Message(str):
     def __new__(cls, msgid: Any, msgtext: Optional[Any] = ..., params: Optional[Any] = ..., domain: str = ..., has_contextual_form: bool = ..., has_plural_form: bool = ..., *args: Any): ...
     def translation(self, desired_locale: Optional[Any] = ...): ...
     def __mod__(self, other: Any): ...

cinder/tests/unit/volume/drivers/test_macrosan_drivers.py

@@ -13,12 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 """Tests for macrosan drivers."""
+from collections import UserDict
 import os
 import socket
 from unittest import mock
 
-from six.moves import UserDict
-
 from cinder import exception
 from cinder.tests.unit import test
 from cinder.volume import configuration as conf

cinder/tests/unit/volume/drivers/test_qnap.py

@@ -15,6 +15,7 @@
 
 import collections
 from unittest import mock
+import urllib
 
 from ddt import data
 from ddt import ddt
@@ -23,8 +24,6 @@ import eventlet
 from lxml import etree as ET
 from oslo_utils import units
 import requests
-import six
-from six.moves import urllib
 
 from cinder import exception
 from cinder.tests.unit import test
@@ -613,7 +612,7 @@ class QnapDriverBaseTestCase(test.TestCase):
     @staticmethod
     def sanitize(params):
         sanitized = {_key: str(_value)
-                     for _key, _value in six.iteritems(params)
+                     for _key, _value in params.items()
                      if _value is not None}
         sanitized = utils.create_ordereddict(sanitized)
         return urllib.parse.urlencode(sanitized)