Update to ioredis 4

Author: nileshmali

package.json

@@ -26,13 +26,13 @@
   },
   "homepage": "https://github.com/fastify/fastify-redis#readme",
   "devDependencies": {
-    "fastify": "^1.2.1",
+    "fastify": "^1.9.0",
     "redis": "^2.8.0",
     "standard": "^11.0.1",
-    "tap": "^11.1.3"
+    "tap": "^12.0.1"
   },
   "dependencies": {
-    "fastify-plugin": "^0.2.2",
-    "ioredis": "^3.2.2"
+    "fastify-plugin": "^1.2.0",
+    "ioredis": "^4.0.0"
   }
 }