Brew: conflicts with: [tap]/[cask] should not tap the missing tap

[max-ae]

Bug report

• [x] ran brew update and can still reproduce the problem?
• [x] ran brew doctor, fixed all issues and can still reproduce the problem?
• [ ] ran brew config and brew doctor and included their output with your issue?

What you were trying to do (and why)

I ran brew update && brew upgrade. Brew then upgraded the calibre cask. Since homebrew/homebrew-cask#91929, the cask contains a conflicts with-statement that got triggered now with a calibre version bump.
The conflicts-with references the homebrew/cask-versions tap. Upgrading the cask lead to said tap being also tapped, despite the need for it.

What happened (include command output)

Ran brew upgrade, then homebrew/cask-versions got unnecessarily tapped

Command output

❯ brew upgrade

==> Casks with auto_updates or version :latest will not be upgraded

==> Upgrading 1 outdated package:

calibre 5.4.2 -> 5.5.0

==> Upgrading calibre

==> Tapping homebrew/cask-versions

What you expected to happen

brew upgrade not to tap homebrew/cask-versions

[MikeMcQuaid]

I agree that references to other taps should not auto-tap them. CC @homebrew/cask for thoughts.