Move Stack on to GHC 9.4.5

[mpilgrem]

Motivation, in part: #6159.

[psibi]

The image for GHC 9.4.5 is pushed to ghcr: https://github.com/fpco/alpine-haskell-stack/pkgs/container/alpine-haskell-stack

I believe something like this work:

docker:
  repo: ghcr.io/fpco/alpine-haskell-stack:9.4.5

[juhp]

(Just FTR: Stackage LTS 21 already has https://www.stackage.org/lts-21.6/package/stack-2.9.3.1)

[mpilgrem]

@juhp, the problem with moving Stack on to GHC 9.4.5 is not that the source code will not compile on some operating systems, but that it will not compile with the versions of GHC 9.4.5 for Alpine Linux (which problems are documented in the associated pull request). The system that builds Stack bindists for Linux is rooted in Alpine Linux - and I don't want to tinker with that system if I can avoid it, for fear of breaking it.

My plan is to see if those problems with GHC were resolved with GHC 9.4.6, released yesterday, once it makes its way on to Nix. I want to release another version of Stack soon, and I'd like to move it on from GHC 9.2.7. However, if GHC remains broken on Alpine Linux, I'll stick with the GHC 9.2 series and move it on to GHC 9.2.8.

[juhp]

Thanks for the explanation - now I understand @psibi's comment better

[benz0li]

I want to release another version of Stack soon, and I'd like to move it on from GHC 9.2.7.

@mpilgrem Is there a timeline for the next Stack release?

I would very much like to include an official, statically linked binary of Stack in my multi-arch (linux/amd64, linux/arm64/v8) glcr.b-data.ch/ghc/ghc-musl Docker images.

[mpilgrem]

@benz0li, Stack is planning to drop its support for GHC 7.10.3 on 13 September 2023. Having done that, I was planning to release Stack 2.13.1 soon after.