Bump redis and machinepack-redis

Bumps [redis](https://github.com/redis/node-redis) and [machinepack-redis](https://github.com/treelinehq/machinepack-redis). These dependencies needed to be updated together.

Updates `redis` from 2.8.0 to 3.1.1
- [Release notes](https://github.com/redis/node-redis/releases)
- [Changelog](https://github.com/redis/node-redis/blob/master/CHANGELOG.md)
- [Commits](redis/node-redis@v.2.8.0...v3.1.1)

Updates `machinepack-redis` from 2.0.6 to 2.0.7
- [Release notes](https://github.com/treelinehq/machinepack-redis/releases)
- [Changelog](https://github.com/sailshq/machinepack-redis/blob/master/CHANGELOG.md)
- [Commits](sailshq/machinepack-redis@v2.0.6...v2.0.7)

---
updated-dependencies:
- dependency-name: redis
  dependency-type: indirect
- dependency-name: machinepack-redis
  dependency-type: indirect
...

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