libphonenumber: remove unused dependencies

[cho-m]

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• Have you checked that there aren't other open pull requests for the same formula update/change?
• Have you built your formula locally with HOMEBREW_NO_INSTALL_FROM_API=1 brew install --build-from-source <formula>, where <formula> is the name of the formula you're submitting?
• Is your test running fine brew test <formula>, where <formula> is the name of the formula you're submitting?
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re2 isn't enabled by default - https://github.com/google/libphonenumber/blob/master/cpp/CMakeLists.txt#L89

• https://github.com/Homebrew/homebrew-core/actions/runs/10733732381/job/29767689263#step:4:218
• https://github.com/Homebrew/homebrew-core/actions/runs/10733732381/job/29767688975#step:5:179