audit: only flag if checksum changes when full url and version stay the same

[dtrodrigues]

• 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?
• 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?
• Have you successfully run brew man locally and committed any changes?

---

This changes the audit to only warn if the url stays the same but the checksum changes. Previously, the audit would trigger if the version is the same but the checksum changed, which may be too restrictive since it's not unexpected for the checksum to change if a different URL is being used. Previous discussion: #9071.

[Rylan12]

One question/suggestion but otherwise looks good (although I haven't had a chance to test it yet)

[Rylan12]

Looks good to me!

Tested locally on vint, nim (the causes of one of the other problems with the audit) and magnetix (one of the formulae with a non-versioned URL and sha256)

[MikeMcQuaid]

Thanks @dtrodrigues!