fix: broken docs test (#11)

* feat: add samples

* fix: npm run lint

* fix: linting

* fix: broken docs test

Author: sofisl

linkinator.config.json

@@ -5,7 +5,8 @@
     "www.googleapis.com",
     "img.shields.io",
     "https://developers.google.com/analytics-admin/",
-    "https://googleapis.dev/nodejs/analytics-admin/latest/index.html"
+    "https://googleapis.dev/nodejs/analytics-admin/latest/index.html",
+    "https://github.com/googleapis/nodejs-analytics-admin/blob/master/samples/quickstart.js"
   ],
   "silent": true,
   "concurrency": 10