Bump redis from 5.0.1 to 5.0.8

Bumps [redis](https://github.com/redis/redis-py) from 5.0.1 to 5.0.8.
- [Release notes](https://github.com/redis/redis-py/releases)
- [Changelog](https://github.com/redis/redis-py/blob/master/CHANGES)
- [Commits](redis/redis-py@v5.0.1...v5.0.8)

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

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

requirements.txt

@@ -10,5 +10,5 @@ pytest-aiohttp==1.0.5
 pytest-cov==4.1.0
 pytest-mock==3.12.0
 pytest-sugar==0.9.7
-redis==5.0.1
+redis==5.0.8
 yarl==1.12.1