Checks GitHub API if homepage 404s during brew audit --online

[troymccabe]

• 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.
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• Have you successfully run brew tests with your changes locally?

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Fixes #13789

[MikeMcQuaid]

Looks good so far! Nice work.

[troymccabe]

🙏 Thanks again for the review! Please lmk if there's anything else that needs to change

[MikeMcQuaid]

Looks good, thanks again @troymccabe!

[troymccabe]

Of course! I'm poking through the other help_wanted issues to see if there's others I can pick up. Has been fun!

Anything I should change on my end for the codecov/project check? Looks like a bunch of unrelated coverage % change in codecov: https://github.com/Homebrew/brew/pull/13907/checks?check_run_id=8472344053

[MikeMcQuaid]

Of course! I'm poking through the other help_wanted issues to see if there's others I can pick up. Has been fun!

Glad to hear it, thanks for contributing!

Anything I should change on my end for the codecov/project check? Looks like a bunch of unrelated coverage % change in codecov: https://github.com/Homebrew/brew/pull/13907/checks?check_run_id=8472344053

No big deal here, mainly for catching actual user logic changes.