chore: upgrade compose-go to v2 beta

[astromechza]

We've been using an ancient version of the compose specification and compose-go types. Much older than any supported docker compose versions. This PR updates us to the latest version that is used by docker itself.

The main change for us is that the services set is now a proper map, rather than an array.

This PR also removes the existing score.yaml and compose.yaml files from the root of the project which were apparently committed by mistake (by me) and are liable to cause confusion.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• New chore (expected functionality to be implemented)

Checklist:

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• I've signed off with an email address that matches the commit author.