WIP: Resolve "Extract EE specific files/lines for config/initializers"

What does this MR do?

Extract EE codes from:

• config/initializers
• config/application.rb

Are there points in the code the reviewer needs to double check?

I haven't figured out how to keep the original require ordering. This would require Rails to sort files based on two directories.

Does this MR meet the acceptance criteria?

• Tests added for this feature/bug
• Conform to the code review guidelines
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #6657 (closed)