brew bump: don't use Repology for versioned formulae

[nandahkrishna]

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

---

This PR proposes to avoid checking Repology for versioned formulae when brew bumping them.

Currently, brew bump's Repology output for a versioned formula shows the latest version for the corresponding non-versioned formula. This leads to incorrect PRs like Homebrew/homebrew-core#94115, Homebrew/homebrew-core#94113, Homebrew/homebrew-core#94110, etc. For example:

➜ brew bump traefik@1
==> traefik@1
Current formula version:  1.7.34
Latest livecheck version: 1.7.34
Latest Repology version:  2.6.0
Open pull requests:       none

With these changes, we have:

➜ brew bump traefik@1
==> traefik@1
Current formula version:  1.7.34
Latest livecheck version: 1.7.34
Latest Repology version:  not found
Open pull requests:       none

The message could probably improved/changed from "not found" for this particular case. I think it's fine to skip Repology altogether because:

• They don't list the versioned formula separately for Homebrew's case (see e.g. https://repology.org/project/traefik/versions, the page contains both traefik and traefik@1).
• Other distributions that have versioned formulae may not use the same name (e.g. Scoop uses traefik1) and searching through all these may be wasteful or include different packages.

This would only be a problem for formulae like openssl where we have only versioned formulae, but there are very few of these, they're usually very popular (Python, OpenSSL, etc.) and livecheck is probably sufficient.

[BrewTestBot]

Review period will end on 2022-02-01 at 09:52:09 UTC.

[BrewTestBot]

Review period skipped due to critical label.

[MikeMcQuaid]

Makes sense to me for now! Agreed with potential for better solutions later.