Bump redis from 4.1.4 to 4.2.0

Bumps [redis](https://github.com/redis/redis-py) from 4.1.4 to 4.2.0.
- [Release notes](https://github.com/redis/redis-py/releases)
- [Changelog](https://github.com/redis/redis-py/blob/master/CHANGES)
- [Commits](https://github.com/redis/redis-py/compare/v4.1.4...v4.2.0)

---
updated-dependencies:
- dependency-name: redis
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -13,6 +13,6 @@ uvloop==0.16.0
 httpx-socks[asyncio]==0.7.2
 langdetect==1.0.9
 setproctitle==1.2.2
-redis==4.1.4
+redis==4.2.0
 mistletoe==0.8.2
 typing_extensions==4.1.1