dependencies: find extraframeworks on case-sensitive filesystems

[reckenrode]

This PR fixes a test failure on case-sensitive filesystems when a CMake dependency is turned into an Apple framework. I ran into this issue while working on the Darwin stdenv in nixpkgs after Meson was updated to 1.4.0 because my Nix store is installed on a case-sensitive APFS volume.

The extraframeworks search logic was already case insensitive. The fix was to use the match’s actual name instead of the one that was requested. I included a test, though the original test for https://github.com/mesonbuild/meson/pull/12181 also serves as a test for case-sensitive filesystems.

I found https://github.com/mesonbuild/meson/issues/12480 in the issue tracker, but the scope of fixing that seems like a much larger fix and wouldn’t address the issue I encountered building the Darwin stdenv in nixpkgs.

[reckenrode]

I fixed the mypy lint failure.

[bruchar1]

ci failures seem irrelevant

[reckenrode]

Is there anything else needing to be done to move this forward after approval?

[abathur]

@jpakkane If I'm following along correctly, it sounds like this would make changes such as #13349 unnecessary :)

[jpakkane]

We are currently in RC freeze so only regression bugfixes are permitted.