M1 (aarch64 darwin) runner support

[elopez]

Hi! GitHub announced M1 runners today: https://github.blog/2023-10-02-introducing-the-new-apple-silicon-powered-m1-macos-larger-runner-for-github-actions/

I tried using this action on one of our repositories (with runs-on: macos-latest-xlarge) but it seems that ghcup chooses to install an intel build for some reason, even though there's an aarch64 one available on the yml metadata. Ideally I would expect it would install the native version of the tools when available. Do you have any idea about what might be going on? Thanks!

Run haskell-actions/setup@v2
  with:
    ghc-version: 9.2
    enable-stack: true
    stack-version: latest
    cabal-version: latest
    cabal-update: true
  env:
    CACHE_VERSION: v6
  
Preparing to setup a Haskell environment
Resolved ghc 9.2 to 9.2.8
Resolved cabal latest to 3.10.1.0
Resolved stack latest to 2.13.1
Preparing ghc environment
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup unset ghc
  [ Info  ] GHC successfully unset
Installing ghc version 9.2.8
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup whereis ghc 9.2.8
  [ Error ] [�
  
  
  Attempting to access tool ghc at location /Users/runner/.ghcup/bin
  Succeeded accessing tool ghc at location /Users/runner/.ghcup/bin
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup set ghc 9.2.8
  [ Info  ] downloading: https://raw.githubusercontent.com/haskell/ghcup-metadata/master/ghcup-0.0.7.yaml as file /Users/runner/.ghcup/cache/ghcup-0.0.7.yaml
    % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                   Dload  Upload   Total   Spent    Left  Speed
  
    0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
  100  306k  100  306k    0     0  4908k      0 --:--:-- --:--:-- --:--:-- 5673k
  [ Error ] [�
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup unset ghc
  [ Info  ] GHC successfully unset
  Attempting to install ghc 9.2.8 using ghcup
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup install ghc 9.2.8
  [ Info  ] downloading: https://downloads.haskell.org/~ghc/9.2.8/ghc-9.2.8-x86_64-apple-darwin.tar.xz as file /Users/runner/.ghcup/tmp/ghcup-95ebcf9d9beaedd5/ghc-9.2.8-x86_64-apple-darwin.tar.xz
    % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                   Dload  Upload   Total   Spent    Left  Speed
  
    0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
   40  169M   40 68.1M    0     0  79.0M      0  0:00:02 --:--:--  0:00:02 79.3M
   84  169M   84  144M    0     0  78.3M      0  0:00:02  0:00:01  0:00:01 78.4M
  100  169M  100  169M    0     0  78.3M      0  0:00:02  0:00:02 --:--:-- 78.5M
  [ Info  ] verifying digest of: ghc-9.2.8-x86_64-apple-darwin.tar.xz
  [ Info  ] Unpacking: ghc-9.2.8-x86_64-apple-darwin.tar.xz to /Users/runner/.ghcup/tmp/ghcup-760615249947cfaa
  [ Info  ] Installing GHC (this may take a while)
  
  
 
  
  
  [ Info  ] Merging file tree from "/Users/runner/.ghcup/tmp/ghcup-4819e735bb1f57fa/Users/runner/.ghcup/ghc/9.2.8" to "/Users/runner/.ghcup/ghc/9.2.8"
  [ Info  ] GHC installation successful
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup set ghc 9.2.8
  [ Warn  ] New ghc version available. If you want to install this latest version, run 'ghcup install ghc 9.6.3'
  [ Info  ] GHC 9.2.8 successfully set as default version
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup whereis ghc 9.2.8
  /Users/runner/.ghcup/ghc/9.2.8/bin/ghc
  
  Attempting to access tool ghc at location /Users/runner/.ghcup/bin
  Succeeded accessing tool ghc at location /Users/runner/.ghcup/bin
  /Users/runner/hostedtoolcache/ghcup/0.1.19.5/arm64/ghcup set ghc 9.2.8
  [ Warn  ] New ghc version available. If you want to install this latest version, run 'ghcup install ghc 9.6.3'
  [ Info  ] GHC 9.2.8 successfully set as default version
  Found ghc 9.2.8 in cache at path /Users/runner/.ghcup/bin. Setup successful.

(full log here)

[elopez]

I was able to get a working build with the changes in #47, example run here