Downgrade @types/node to match mqtt.js

Author: bdchauvette

package-lock.json

@@ -29,7 +29,7 @@
     "mqtt": "^2.3.1"
   },
   "devDependencies": {
-    "@types/node": "^10.12.10",
+    "@types/node": "^8.10.21",
     "eslint": "^4.8.0",
     "mqtt-connection": "^3.0.0",
     "tape": "^4.6.3"