Introduce python_major_minor_version DSL

[iMichka]

This is a shorthand version for Language::Python.major_minor_version

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[iMichka]

Cc @MikeMcQuaid

[Copilot]

Pull request overview

Adds a new Formula DSL helper in Language::Python::Virtualenv to expose Language::Python.major_minor_version via a shorter call site, plus a spec to verify delegation.

Changes:

• Introduce python_major_minor_version(python) as a delegating DSL helper for formulas including Language::Python::Virtualenv.
• Add an RSpec example asserting the helper delegates to Language::Python.major_minor_version.

Reviewed changes

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

File	Description
Library/Homebrew/language/python.rb	Adds a new public DSL helper method delegating to Language::Python.major_minor_version.
Library/Homebrew/test/language/python/virtualenv_spec.rb	Adds a spec covering the new helper method’s delegation behavior.

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[iMichka]

Waiting for the discussion in #23479 (comment) to finish, as we might go in another direction

[MikeMcQuaid]

Thanks!