Fix more test failures

[cho-m]

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More test failure fixes.

https://github.com/Homebrew/homebrew-core/actions/runs/29278992918/job/86917281683?pr=292807#step:3:231

  Error: Cask::Caskroom.casks does not list a cask twice when it is also installed under an old token
  
  Failure/Error: expect(described_class.casks.map(&:token)).to eq(["new-cask"])
  
    expected: ["new-cask"]
         got: ["new-cask", "old-cask"]

https://github.com/Homebrew/homebrew-core/actions/runs/29278992918/job/86917281683?pr=292807#step:3:100

  Error: MacOSVersion::kernel_major_version matches the major version returned by OS.kernel_version
  
  Failure/Error: expect(described_class.kernel_major_version(OS::Mac.version)).to eq OS.kernel_version.major
  
    expected: #<Version::NumericToken 21>
         got: #<Version 20>

[Copilot]

Pull request overview

This PR adjusts Homebrew’s RSpec suite to address two observed CI failures by making the affected specs more deterministic in environments with global macOS simulation settings and parallel trust-store interactions.

Changes:

• Unset HOMEBREW_FAKE_MACOS in the MacOSVersion.kernel_major_version spec to ensure it matches the real OS.kernel_version on macOS runners.
• Run the caskroom “old token” de-duplication spec under the :trust_store shared context to isolate the trust store per example.

Reviewed changes

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

File	Description
Library/Homebrew/test/macos_version_spec.rb	Ensures the kernel-major-version assertion isn’t affected by globally-set HOMEBREW_FAKE_MACOS.
Library/Homebrew/test/cask/caskroom_spec.rb	Runs the cask rename/de-duplication spec with isolated trust-store state to avoid cross-test interference.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.