Invalidate bottle cache for local patches

[MikeMcQuaid]

• Include local patch paths when checking formula changes.
• Prevent stale bottles when a patch changes without its formula.
• Cover the cache decision with a regression test.

Fixes #23588

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[Copilot]

Pull request overview

This PR updates Homebrew’s test-bot bottle-cache invalidation logic so that a cached bottle is considered invalid not only when the formula file changes, but also when any local patch file referenced by the formula changes. This addresses stale-bottle reuse when only a local patch has been modified.

Changes:

• Extend no_diff? to include local patch file paths (from formula.patchlist) in the git diff pathspec used to decide cache validity.
• Add a regression spec ensuring artifact_cache_valid? rejects a cached bottle when only a local patch file has changed.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
Library/Homebrew/test_bot/test_formulae.rb	Include local patch paths in the git diff check that underpins bottle-cache validity decisions.
Library/Homebrew/test/test_bot/test_formulae_spec.rb	Add regression coverage for invalidating the artifact cache when a local patch changes without the formula changing.

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