test: fix typescript test (#97)

Author: climba03003

package.json

@@ -25,14 +25,15 @@
   ],
   "homepage": "https://github.com/fastify/fastify-oauth2#readme",
   "devDependencies": {
+    "@types/node": "^15.6.1",
     "fastify": "^3.0.3",
     "nock": "^13.0.0",
     "pre-commit": "^1.2.2",
     "simple-get": "^4.0.0",
     "snazzy": "^9.0.0",
     "standard": "^16.0.0",
     "tap": "^15.0.0",
-    "tsd": "^0.11.0"
+    "tsd": "^0.16.0"
   },
   "dependencies": {
     "fastify-plugin": "^3.0.0",