3.3.1-RC2 Release procedure

[Kordyjan]

• Backport relevant fixes:
  • Dealias types in New before matching quotes #17615
    • Backport #17615 #17749
  • Fix accessibleType for package object prefixes #18057
    • Backport "Fix accessibleType for package object prefixes" #18088
• Publish artifacts to Maven via CI
  • On release-3.3.1 branch:
    • In Build.scala: Set baseVersion to 3.3.1-RC2
    • In Build.scala: Set previousDottyVersion to 3.3.1-RC1
    • in changelogs add file with a changelog
    • Tag the branch as 3.3.1-RC2
  • https://github.com/lampepfl/dotty/actions/runs/5401953891
• On main:
  • In Build.scala: Set referenceVersion to 3.3.1-RC2
  • Set reference version to 3.3.1-RC2 #18146
• Announce the release
  • Publish release on GitHub Releases
  • Comment on the announcement thread on https://contributors.scala-lang.org