Release cardano-ledger-[alonzo|babbage]-1.2.1

[lehins]

Description

This PR prepares a release with backported fix implemented in #3440

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)
• 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)
• 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

[JaredCorduan]

if this is a backport, shouldn't it be targeting release/plutus_v3 instead of master?

[lehins]

if this is a backport, shouldn't it be targeting release/plutus_v3 instead of master?

Yes, it should. Thank you. I did use it as base

[JaredCorduan]

looks great, thank you!