[Bug] Error: Ember is not defined(Ember ~v4.4.0) in production builds

[Windvis]

Describe the bug

We're running into the exact same issue as #103 with the exception that in only happens when creating a production build of the "dummy" app.

Steps to reproduce the behavior

1. set up Storybook in an Ember v4 based addon blueprint
2. run ember build --environment=production to create a production build of the dummy app
3. run build-storybook
4. serve the final output npx http-server ./storybook-static
5. open a Story that contains a component
6. The Ember is not defined message will be shown in the preview section

Expected behavior

The component is rendered as normal.

Environment

• Node.js version: 14.20.1
• NPM version: 6.14.17

Additional context

This check fails because assets/vendor.js does not exist in production builds. The file will contain a hash instead: assets/vendor-some-hash-1234.js.