chore(deps): update dependency @types/node to v8.5.6

Author: renovate-bot

package.json

@@ -18,7 +18,7 @@
     "reify": "^0.13.5"
   },
   "devDependencies": {
-    "@types/node": "8.5.5",
+    "@types/node": "8.5.6",
     "tslint": "5.8.0",
     "typescript": "2.6.2"
   }