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>