[cho-m]

I applied a Copilot suggestion back in prior PR to use cached_download but this causes slowdown in tests when download doesn't exist. I think it tries to access url via curl to resolve filename from headers.

So mock a value to avoid increasing testcase time.

Prior to this, brew tests --only formula --profile 5 would have 3 of these hit 7+ seconds making them significantly slower than rest. After changes, these no longer show up in slowest tests.

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n/a

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[Copilot]

Copilot review overview

🟢 Approval recommended

No unresolved review comments remain.

Review effort: Lite
Findings: None

What changed in this PR

Updates formula_spec to avoid slow download resolution in std_go_args tests.

Changes:

• Uses a realistic tarball URL.
• Mocks cached downloads and Git metadata lookups.
• Preserves coverage for revision and repository cases.

File	Description
Library/​Homebrew/​test/​formula_spec.rb	Speeds up tests with deterministic download mocks.

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[MikeMcQuaid]

Thanks!