Support GHC 9.4

[lrworth]

A more conservative approach than https://github.com/dhall-lang/dhall-haskell/pull/2496. Older versions of libraries should still work, and the behaviour on windows should not have changed at all (except for the error string).

I was able to build dhall with GHC 8.10 and 9.4; I don't have time to update the other packages.

Closes #2537.

[lrworth]

All the check failures seem to be related to a 504 when fetching https://httpbin.org/user-agent. I don't know how to resolve that.

[Gabriella439]

Sorry for the delay on this. I've put up a PR to disable the httpbin.org-related tests:

https://github.com/dhall-lang/dhall-haskell/pull/2533

… and once that merges then it will hopefully unblock your PR

[georgefst]

Note that this works for GHC 9.6 as well with --allow-newer='cborg-json:base,dhall:template-haskell'. At least for the core dhall library.

In other words, the library's bound on template-haskell needs bumping (though cabal oudated suggests many other bumps that wouldn't hurt), and then we're just blocked on https://github.com/well-typed/cborg/pull/313.

[georgefst]

Could we possibly get a Hackage patch release with this and other recent dependency fixes? I'm unfortunately a bit stuck because of a use of dhall in a cabal script, and those don't yet support source-repository-package stanzas (https://github.com/haskell/cabal/issues/8024#issuecomment-1441185774).

[georgefst]

In other words, the library's bound on template-haskell needs bumping

Hopefully, this will be merged via https://github.com/dhall-lang/dhall-haskell/pull/2542.

[georgefst]

Looks like this was released via https://github.com/dhall-lang/dhall-haskell/pull/2545. Thanks @Gabriella439!

[Gabriella439]

You're welcome! 😊