Bump redis from 5.0.8 to 5.1.0 (#401)

Bumps [redis](https://github.com/redis/redis-rb) from 5.0.8 to 5.1.0.
- [Changelog](https://github.com/redis/redis-rb/blob/master/CHANGELOG.md)
- [Commits](https://github.com/redis/redis-rb/compare/v5.0.8...v5.1.0)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -276,7 +276,7 @@ GEM
       ffi (~> 1.0)
     rdoc (6.6.2)
       psych (>= 4.0.0)
-    redis (5.0.8)
+    redis (5.1.0)
       redis-client (>= 0.17.0)
     redis-client (0.19.1)
       connection_pool