csound: fix building with Ableton Link

[nwhetsell]

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This PR updates the Ableton Link resource to the latest commit, which doesn’t use functions that were removed in ASIO v1.33. (I tried to apply that commit as a patch, but the patch didn’t apply cleanly.)

While we’re at it, also

• Restore a test of the existence of Faust features. This test was removed in c1413ac because Faust features are causing a segmentation fault when used with FluidSynth, but it’s possible to check that Faust is present without running it.
• Change the HEAD branch to develop (so that the formula passes brew audit --strict --online).

[nwhetsell]

I’ve also added a patch for an apparently incorrect member variable name. The code that’s causing the build failure seems to have been around since 2021; I’m very unsure how this was ever working. I also don’t know if a patch is the best way to fix this.

[nwhetsell]

It looks like the build failure was due to an intermittent issue with downloading from GitHub. (The resource that failed to download is a patch that was added to the formula in 2022.)

[calvinit]

Just wondering — once it’s merged, would that help with the CI deps check failing on #212057?

• https://github.com/Homebrew/homebrew-core/actions/runs/15011448707/job/42181963161#step:3:1372

[nwhetsell]

It should, the Csound build in openjdk errors with Ableton Link, and that error is what this PR is intended to address.

[SMillerDev]

Thanks @nwhetsell ! Without contributions like yours it'd be impossible to keep homebrew going with the high standards that users have come to expect from the project. You can feel good knowing that you've made the world a tiny bit better for homebrew users around the world! 👍 🎉