autoremove: handle runtime dependencies

[wu21-web]

Fixes #21511

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• AI was used to generate or assist with generating this PR. Please specify below how you used AI to help you, and what steps you have taken to manually verify the changes.
  Yes. Github Copilot was used in some debugging and styling modifications. I came up with the fix. I referenced sobert docs to verify the changes applied.

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I noticed that the previous solution of modifying cleanup.rb in /Library/Homebrew/cmd and /Library/Homebrew/ is over-complicated and incorrect. Modifying autoremove.rb in libutils would be much easier.

[MikeMcQuaid]

Looks good so far! Please keep this in the same PR and don't open new PRs, instead just squash your history if things get messy.

[MikeMcQuaid]

@wu21-web please ensure you:

• review all AI generated code locally before you push
• please don't have you and/or the AI add more obvious comments

[wu21-web]

OK. Thanks for the tip.

[wu21-web]

@MikeMcQuaid Hi! Job 63646434598 is failing because Homebrew already has formulae installed when the workflow runs. We have to modify the test.yml to include with.uninstall = true to remove pre installed brew formulas.