Bump redis from 3.3.11 to 3.4.1

Bumps [redis](https://github.com/andymccurdy/redis-py) from 3.3.11 to 3.4.1.
- [Release notes](https://github.com/andymccurdy/redis-py/releases)
- [Changelog](https://github.com/andymccurdy/redis-py/blob/master/CHANGES)
- [Commits](redis/redis-py@3.3.11...3.4.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

requirements.txt

@@ -1,7 +1,7 @@
 tornado==5.0.2 # Because https://stackoverflow.com/questions/55452074/bokeh-serve-show-myapp
 lxml==4.4.2
 python-dotenv==0.12.0
-redis==3.3.11
+redis==3.4.1
 schedule==0.6.0
 requests==2.22.0
 pycurl==7.43.0.5