remove unnecessary ioredis package

services/real-time/package.json

@@ -15,7 +15,6 @@
     "cookie-parser": "^1.3.3",
     "express": "^4.10.1",
     "express-session": "^1.9.1",
-    "ioredis": "^2.4.0",
     "logger-sharelatex": "git+https://github.com/sharelatex/logger-sharelatex.git#v1.1.0",
     "metrics-sharelatex": "git+https://github.com/sharelatex/metrics-sharelatex.git#v1.4.0",
     "redis-sharelatex": "git+https://github.com/sharelatex/redis-sharelatex.git#v1.0.4",