Review PR #13844 for functionality.

Does V2 really work?

Reason to have it put to a milestone: When we release the alpha, all users will have updated their study.yml thing. If something does not work, we might be need study version 3; which I don't want to include.

Reason: In main branch there should be a "working" thing and not something broken.

I volunteered to check for myself, but maybe others interested in SLR (@InAnYan) could try out.

checklist

• version file semvered
• study.yml following the new format added to test cases
• SLR: Add reasoning on databases/catalogs #12631 handled?
• Introduce catalog-specific queries #12639 handled?