sprocket-rails adds some precompile assets we actually do not need.

It copies all _non_ js and CSS files from the app/assets/ older.

In our case this copies for example: Vue, Markdown and Graphql, which we
do not need for production.

We remove this default behavior and then reimplement it in order to
consider ee/ as well and remove those other files we do not need.

For reference: https://github.com/rails/sprockets-rails/blob/v3.2.1/lib/sprockets/railtie.rb#L84-L87