Fix test-bot links in documentation

[dnicolson]

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[Copilot]

Pull request overview

Updates Homebrew’s documentation to point brew test-bot references at the correct source file in the Homebrew/brew repository, improving link accuracy for readers looking up implementation details.

Changes:

• Update External-Commands.md to link to the in-repo dev-cmd/test-bot.rb file.
• Update BrewTestBot.md to link to the same in-repo dev-cmd/test-bot.rb file instead of the external repository.

Reviewed changes

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

File	Description
docs/External-Commands.md	Fixes the brew test-bot example link to point at the in-repo command implementation.
docs/BrewTestBot.md	Updates the test-bot.rb link to the in-repo implementation.

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[ZhongRuoyu]

Good catch, thanks!

[MikeMcQuaid]

Thanks!