formula_versions: typed: strict

[cho-m]

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[Copilot]

Pull request overview

This PR converts Library/Homebrew/formula_versions.rb from typed: true to typed: strict Sorbet mode, adding comprehensive type annotations throughout the file to satisfy stricter type checking requirements.

Key Changes:

• Updated Sorbet sigil from typed: true to typed: strict
• Added T.let type annotations for all instance variables in the initializer
• Added type signatures for attr_reader methods and the nostdout helper method
• Enhanced the rev_list method signature to properly type the block parameter

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[MikeMcQuaid]

Thanks again @cho-m!