Bump redis from 3.4.0 to 3.4.1 (#312)

Author: dependabot-preview[bot]

requirements.txt

@@ -2,6 +2,6 @@ cherry_picker==1.3.2
 aiohttp==3.6.2
 gidgethub==3.3.0
 cachetools==4.0.0
-redis==3.4.0
+redis==3.4.1
 celery==4.4.0
 sentry-sdk==0.14.1