audit: avoid python symlink conflict

[Rylan12]

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Resolves #8949

Only allow one python formula to create pip3 and wheel3 symlinks

CC: @fxcoudert, @SMillerDev and @MikeMcQuaid

[MikeMcQuaid]

Thanks for this @Rylan12! I think this is a good test but I wonder if it's overly specific and we'd be better looking at the actually written symlinks in brew audit instead. Thoughts? ✅ because this is better than the status quo and we could consider having both approaches.

[Rylan12]

I think the benefit of checking the actual symlinks in brew audit is it checks the actual links rather than the code that generates the links (which could change rendering this check pretty useless). So, going with an audit is probably a better solution. I'll look into it in about an hour when I've got some more time.

In terms of specificity, what would the less specific audit be? As far as I know, this is the only formula with this kind of symlink issue. The problem is inherently specific because we do want to allow some symlinks (e.g. pip3.x) but not all symlinks (e.g. pip3)

[MikeMcQuaid]

In terms of specificity, what would the less specific audit be?

Sorry, to be clear, I thought this RuboCop was overly specific (due to the reasons you stated yourself) but any brew audit checking these symlinks would not be problematically specific 👍🏻