We have a web application in App Engine. I was wondering whether it is a good idea to move my static resources (i.e Images, CSS files, and JS files) out from App Engine and serv
You are right, and the answer you accepted is wrong. The answer to your question from the official docs:
https://cloud.google.com/storage/docs/website-configuration
Hosting static assets for a dynamic website
You can use a Google Cloud Storage to host static assets for a dynamic website hosted, for example, in Google App Engine or in Google Compute Engine. Some benefits of hosting your static assets, like images or Javascript files, in a bucket include: