[FEATURE] Make app.static_folder point to app.config['STATIC_FOLDER']

[DUOLabs333]

Describe the feature you'd like to see added
Right now, app.static_folder is hardcoded to point within inside the module folder. This makes it hard to make it portable (or in my case, package whoogle as a zipapp), as Flask looks inside app.static_folder+'/build' instead of app.config['BUILD_FOLDER']. app.config['STATIC_FOLDER'] is much more portable.

Additional context
Add any other context or screenshots about the feature request here.