Remove trailing whitespaces

Author: dojutsu-user

readthedocs/settings/base.py

@@ -390,7 +390,7 @@ def USE_PROMOS(self):  # noqa
                 'filename': os.path.join(LOGS_ROOT, 'debug.log'),
                 'formatter': 'default',
             },
-            'null': {   
+            'null': {
                 'class': 'logging.NullHandler',
             },
         },