Change how SPO votes are counted

[Lucsanszky]

Description

Resolves #4645

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated
• All visible changes are prepended to the latest section of a CHANGELOG.md for the affected packages.
  New section is never added with the code changes. (See RELEASING.md)
• When applicable, versions are updated in .cabal and CHANGELOG.md files according to the
  versioning process.
• The version bounds in .cabal files for all affected packages are updated.
  If you change the bounds in a cabal file, that package itself must have a version increase. (See RELEASING.md)
• Code is formatted with fourmolu (use scripts/fourmolize.sh)
• Cabal files are formatted (use scripts/cabal-format.sh)
• hie.yaml has been updated (use scripts/gen-hie.sh)
• Self-reviewed the diff

[lehins]

This is looking good

[Lucsanszky]

I had to disable the ratify conformance test until IntersectMBO/formal-ledger-specifications#578 is resolved, since now the spec and the implementation differs with regards to the SPO vote counts. I managed to tweak the SPO votes for conformance tests to make the tests pass until the spec is up-to-date. I'll probably add some more comments why I needed to adjust some of the stake amounts in pools for the tests (electBasicCommittee registers a stake pool and with the vote count changes we didn't always reach the threshold post-bootstrap). Other than that, this is ready for review and I'll add some tests in a separate PR.

[teodanciu]

Looks good to me, but will let @lehins approve since this is is performance-sensitive Umap stuff.

[lehins]

This looks great!
We'll definitely need to a few Imp tests for this and re-enable RATIFY conformance test once spec catches up.
But, it is definitely OK to postpone that work until after this PR is merged.

[Lucsanszky]

This looks great! We'll definitely need to a few Imp tests for this and re-enable RATIFY conformance test once spec catches up. But, it is definitely OK to postpone that work until after this PR is merged.

Sounds good! I managed to tweak the conformance tests to filter for Abstain votes for SPOs, which is slightly better than disabling the RATIFY conformance tests altogether.