Update the list of GHC extension for GHC 9.2 and 9.4

[Mikolaj]

This should not be to hard, based on GHC release notes or user guide, and should go in file Cabal-syntax/src/Language/Haskell/Extension.hs. I don't know if any extensions from 9.2 are missing, or perhaps even 9.0, so worth checking all.

[ffaf1]

A note for future updates, Overview of all language extensions is sadly not exhaustive (e.g. see DoAndIfThenElse is undocumented).

[ffaf1]

I did not include undocumented language extensions AlternativeLayoutRule, AlternativeLayoutRuleTransitional, RelaxedLayout.

[Mikolaj]

Thank you!

Is there a chance somebody is using the undocumented extensions and cabal would yell at that person? If it yells, should it yell "unknown or undocumented in GHC user manual" instead of the current (I assume) "uknown"?