Bump redis from 2.8.0 to 3.1.1

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

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

package.json

@@ -73,7 +73,7 @@
     "lodash": "^4.17.11",
     "mysql": "^2.16.0",
     "pg": "^8.0.3",
-    "redis": "^2.8.0",
+    "redis": "^3.1.1",
     "uuid": "^3.3.2",
     "validator": "^10.11.0"
   },