chore(package): update ioredis to version 4.11.2

package.json

@@ -32,7 +32,7 @@
     "assume": "~2.2.0",
     "async": "~3.1.0",
     "binary-pack": "~1.0.2",
-    "ioredis": ">=4.0.0",
+    "ioredis": ">=4.11.2",
     "istanbul": "~0.4.5",
     "metroplex": "~1.0.0",
     "mocha": "~6.1.2",