apache-arrow: use ENV.runtime_cpu_detection

[carlocab]

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Also, add a utf8proc dependency. The build vendors its own otherwise.

Closes #76537

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Needs Homebrew/brew#11608 to land in a brew release before merging.

[carlocab]

ENV.runtime_cpu_detection is in https://github.com/Homebrew/brew/releases/tag/3.2.1.

[BrewTestBot]

@carlocab has triggered a merge.

[Rylan12]

@carlocab all ENV.runtime_cpu_detection calls will be gates by an if Hardware::CPU.intel?, right? What happens if you call it on ARM, do things break? I almost wonder if it just makes more sense to make it a no-op on ARM so it doesn't need the if statements

[carlocab]

Not necessarily -- I think it should also be safe (and desirable) to use unconditionally for formulae like openblas. I just don't know of a good way to actually inspect the binary objects to check that it probably does the right thing on ARM.