Add DRep to UMap, Rename Trip to UElem

[aniketd]

Description

• Add DReps to UMap
• Rename Trip to UElem, and the pattern Triple to UElem
• Validate the equivalence of unionRewAgg and unionKeyRewards with the help of property tests, and remove one implementation between them.

This property test has been retained in the history of the branch

[nix-shell:~/Code/_iog/cardano-ledger/vdelegs-in-umap]$ cabal test cardano-ledger-core --test-options '-m unionKeyRewards -a 10000 --qc-max-size 1000'
Build profile: -w ghc-9.2.7 -O1
In order, the following will be built (use -v for more details):
 - cardano-ledger-core-1.3.0.0 (test:tests) (ephemeral targets)
Preprocessing test suite 'tests' for cardano-ledger-core-1.3.0.0..
Building test suite 'tests' for cardano-ledger-core-1.3.0.0..
Running 1 test suites...
Test suite tests: RUNNING...

Core
  UMap
    unionRewAgg === unionKeyRewards
      unionRewAgg === unionKeyRewards [✔] (55383ms)
        +++ OK, passed 10000 tests.

Finished in 55.3837 seconds
1 example, 0 failures
Test suite tests: PASS
Test suite logged to:
/home/aniketd/Code/_iog/cardano-ledger/vdelegs-in-umap/dist-newstyle/build/x86_64-linux/ghc-9.2.7/cardano-ledger-core-1.3.0.0/t/tests/test/cardano-ledger-core-1.3.0.0-tests.log
1 of 1 test suites (1 of 1 test cases) passed.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated
• 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 (See RELEASING.md)
• Any changes are noted in the latest section of a CHANGELOG.md for the affected packages. New section is never added with the code changes. (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]

Looks awesome!

It would be great if @TimSheard could give it a review, since he is much more familiar with UMap.

[JaredCorduan]

this is great, thanks @aniketd !

[JaredCorduan]

The golden test failure in CI is expected, since we changed the ledger state serialization in this PR. So we just need to regenerate the golden files.

[lehins]

Awesome work