Move all `spec/ee/spec/*` files to `ee/spec/`

What does this MR do?

This moves all the EE-specific test files located under spec/ee/spec to ee/spec.

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

For now I've create a new job for EE-specific tests. This job doesn't use Knapsack but depending on its duration we may need to setup a dedicated knapsack report for these specs...

Why was this MR needed?

To continue extracting EE-specific files to the top-level ee/ folder (&27 (closed)).

Does this MR meet the acceptance criteria?

• Tests added for this feature/bug
• Review
  • Has been reviewed by Backend
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• End-to-end tests pass (package-qa manual pipeline job)

What are the relevant issue numbers?