audit: add require utils/backtrace

[Moisan]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
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Spotted in https://github.com/Homebrew/homebrew-core/actions/runs/9942660636/job/27464770982?pr=177398

> brew audit --formula gnu-typist --online --git --skip-style output
  Error: uninitialized constant Utils::Backtrace

[Moisan]

#17762 covers this more globally.