add ghc-9.2.1-alpha1

https://discourse.haskell.org/t/ghc-9-2-1-alpha1-now-available/2286

Noteworthy but non-blocking:

• (unofficial) i386 alpine bindist missing
• ARM bindists use debian 10 (instead of 9)
• FreeBSD bindist missing

CI failure seems to be unrelated.

ghc: could not execute: hspec-discover

Maybe using build-tool-depends like this

build-tool-depends:
  hspec-discover:hspec-discover

instead of installing it manually fixes the issue?

Thanks, although I had already done it manually (didn't push yet).

closed