Add exception for veclibfort linking to Accelerate

[zbeekman]

• veclibfort exists solely to wrap Apple's accelerate and provide BLAS/LAPACK
  access to Accelerate

• Improve the help message for that audit to mention veclibfort

• See discussion in audit: check Accelerate linkage for core formulae #6130

• 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?

Add an Accelerate linkage audit exception for veclibfort since its raison d'etre is to wrap accelerate.

• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew tests with your changes locally?

---

[zbeekman]

@MikeMcQuaid @jonchang no idea why the linux check is failing.

[MikeMcQuaid]

@zbeekman Did you read the output? The reason seems pretty clear to me.

[MikeMcQuaid]

https://dev.azure.com/Homebrew/Homebrew/_build/results?buildId=9351&view=logs&jobId=0da5d1d9-276d-5173-c4c4-9d4d4ed14fdb&taskId=6c56d998-158d-5232-283c-5140104799fc&lineStart=498&lineEnd=516&colStart=1&colEnd=1

[zbeekman]

@MikeMcQuaid Yup, read the output and saw that, however, I did NOT touch the file with the audit failure! I can look into fixing it, even though I didn't introduce the audit failure.

[MikeMcQuaid]

@zbeekman Ok, I see now. I think it was a RuboCop bump happening before another PR was merged. Thanks for fixing it 🎉

[MikeMcQuaid]

Thanks @zbeekman!