Allow to run pep8/docs tox env with horizon plugins

As of now, when horizon plugins are configured in the horizon repo,
pep8 and docs tox env cannot run.
This is because openstack_dashboard.settings tries to load horizon plugins
but horizon plugins are not installed in tox env by default and
the jobs will fail as a result.
This commit changes to use openstack_dashboard.test.settings
as DJANGO_SETTINGS_MODULE for these tox environments by default.

Change-Id: I6a9d0c74271cc4addd8a0964b5955d7d3b6d8267

doc/source/conf.py

@@ -45,7 +45,8 @@ ROOT = os.path.abspath(os.path.join(BASE_DIR, "..", ".."))
 sys.path.insert(0, ROOT)
 
 # This is required for ReadTheDocs.org, but isn't a bad idea anyway.
-os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'openstack_dashboard.settings')
+os.environ.setdefault('DJANGO_SETTINGS_MODULE',
+                      'openstack_dashboard.test.settings')
 
 django.setup()
 

tox.ini

@@ -56,6 +56,9 @@ basepython = python3
 deps =
   {[testenv]deps}
   -r{toxinidir}/doc/requirements.txt
+setenv =
+  {[testenv]setenv}
+  DJANGO_SETTINGS_MODULE=openstack_dashboard.test.settings
 commands =
   flake8 {posargs}
   {envpython} {toxinidir}/manage.py extract_messages --verbosity 0 --check-only