Fixes typo

funtests/stress/stress/templates.py

@@ -70,7 +70,7 @@ class default(object):
 class redis(default):
     BROKER_URL = os.environ.get('CSTRESS_BROKER', 'redis://')
     CELERY_RESULT_BACKEND = os.environ.get(
-        'CSTRESS_bACKEND', 'redis://?new_join=1',
+        'CSTRESS_BACKEND', 'redis://?new_join=1',
     )
     BROKER_TRANSPORT_OPTIONS = {'fanout_prefix': True}