Plumb GH_TOKEN to Acquisition outerloop/integration tests via test properties bag

[radical]

Summary

The Acquisition test project (tests/Aspire.Acquisition.Tests) includes outerloop integration tests (PRScriptIntegrationTests) that require GH_TOKEN to call real GitHub APIs. Currently, the token is not provided to these tests when run in the outerloop workflow.

In PR #15995, we removed the || inputs.testShortName == 'Acquisition' special-case from run-tests.yml to avoid unnecessarily exposing GH_TOKEN to the normal (non-outerloop) Acquisition tests, which use mock gh scripts and don't need the token.

What's Needed

Once #16056 (generic properties bag for test pipeline) is merged, add a requiresGhToken MSBuild property to the Acquisition test project so the outerloop workflow can provide GH_TOKEN without hardcoding test names in the workflow YAML.

Blocked By

• Simplify test pipeline flag plumbing with a generic properties bag #16056 — Simplify test pipeline flag plumbing with a generic properties bag

Context

• PR Add comprehensive test coverage for CLI acquisition scripts #15995 — Add comprehensive test coverage for CLI acquisition scripts
• The outerloop integration tests self-skip gracefully when GH_TOKEN is absent (Assert.Skip), so this is not blocking any CI runs.