dev-cmd/tap-new: use ubuntu-latest + ghcr.io/homebrew/brew:main

[cho-m]

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Similar to how we run in homebrew/core, set up tap with ubuntu-latest and ghcr.io/homebrew/brew:main which reduce 3rd party maintenance after migration or after GitHub drops support for older Ubuntu.

Would still need to update macOS versions but unavoidable as Intel macOS only has versioned runner labels.

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Can't comment on performance. May be slower due to fetching container.

[Copilot]

Pull request overview

Updates the brew tap-new generated GitHub Actions workflows to follow Homebrew’s current Linux CI pattern by using the floating ubuntu-latest runner with the ghcr.io/homebrew/brew:main container, reducing maintenance when GitHub deprecates specific Ubuntu runner versions.

Changes:

• Switch the generated tests.yml Linux job to run on ubuntu-latest using ghcr.io/homebrew/brew:main via a matrix include.
• Switch the generated publish.yml (pr-pull) job to ubuntu-latest and run inside ghcr.io/homebrew/brew:main.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 2 comments.

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[MikeMcQuaid]

Makes sense, thanks!