helix: improve test

[aslilac]

• Have you followed the guidelines for contributing?
• Have you ensured that your commits follow the commit style guide?
• Have you checked that there aren't other open pull requests for the same formula update/change?
• Have you built your formula locally with 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?
• Does your build pass brew audit --strict <formula> (after doing brew install --build-from-source <formula>)? If this is a new formula, does it pass brew audit --new <formula>?

---

hx --health does a much more thorough "things are working" test than just printing out the help info, so let's do that instead!

[chenrui333]

why not merge this into #109423?

[aslilac]

I can do it as one PR if you prefer, I just thought they were unrelated enough for two 🤷‍♀️

[chenrui333]

I can do it as one PR if you prefer, I just thought they were unrelated enough for two 🤷‍♀️

sure, no problem.