Constraint flake8 and pyflakes versions

Versions of flake8 and pyflakes to be installed are inherited from
somewhere, which may be dangerous. Therefore the patch adds their
versions explicitly to test-requrirements.txt file.

Change-Id: I7c54407f6013c4c87fef4258cf963e393bea45b9

config_tempest/tests/base.py

@@ -255,13 +255,13 @@ class BaseServiceTest(base.BaseTestCase):
         FAKE_V3_EXTENSIONS = (
             {
                 'resources': {
-                    URL + 'OS-INHERIT/1.0/rel/domain_user_'
-                        + 'role_inherited_to_projects': "",
+                    URL + 'OS-INHERIT/1.0/rel/domain_user_' +
+                          'role_inherited_to_projects': "",
 
                     URL + 'OS-SIMPLE-CERT/1.0/rel/ca_certificate': "",
 
-                    URL + 'OS-EP-FILTER/1.0/rel/endpoint_group_to_'
-                        + 'project_association': "",
+                    URL + 'OS-EP-FILTER/1.0/rel/endpoint_group_to_' +
+                          'project_association': "",
 
                     URL + 'OS-EP-FILTER/1.0/rel/project_endpoint': "",
 

test-requirements.txt

@@ -3,7 +3,8 @@
 # process, which may cause wedges in the gate later.
 
 hacking>=0.12.0,<0.13 # Apache-2.0
-
+pyflakes>=0.8,<=2.0.0 # MIT
+flake8<3.0.0 # MIT
 coverage>=4.0 # Apache-2.0
 python-subunit>=0.0.18 # Apache-2.0/BSD
 oslotest>=1.10.0 # Apache-2.0