bump ioredis

libraries/redis-wrapper/package.json

@@ -8,7 +8,7 @@
   "dependencies": {
     "async": "^2.5.0",
     "coffee-script": "1.8.0",
-    "ioredis": "~4.6.0",
+    "ioredis": "~4.9.1",
     "redis-sentinel": "0.1.1",
     "underscore": "1.7.0"
   },