Fix Sphinx settings module OS env variables

docs/conf.py

@@ -20,7 +20,9 @@ import django
 from django.conf import settings
 
 sys.path.insert(0, os.path.abspath('..'))
-os.environ['DJANGO_SETTINGS_MODULE'] = 'SciPost_v1.settings'
+
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "SciPost_v1.settings")
+
 #settings.configure()
 django.setup()