[Flaky Test] Microsoft.Build.UnitTests.CodeTaskFactoryTests.RedundantMSBuildReferences

**Flaky-test key** (automated de-duplication — do not edit):
```text
flaky-test-id: Microsoft.Build.UnitTests.CodeTaskFactoryTests.RedundantMSBuildReferences
```

## Evidence

- **Distinct sources:** 3 (0 PRs + 3 rolling builds)
- **Rolling builds:** [1514373](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1514373), [1517682](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1517682), [1527742](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1527742)
- **Legs:** FullOnWindows Release
- **TFMs:** net472
- **Assembly:** Microsoft.Build.Tasks.UnitTests
- **First seen:** 2026-07-17 | **Last seen:** 2026-07-27

## Sample error

```
Assert.True() Failure
Expected: True
Actual: False
```

## Fully-qualified test name

`Microsoft.Build.UnitTests.CodeTaskFactoryTests.RedundantMSBuildReferences`

Source: `src/Tasks.UnitTests/CodeTaskFactoryTests.cs`

## Next steps

This test will be quarantined via `[ActiveIssue("https://github.com/dotnet/msbuild/issues/")]` (from `Microsoft.DotNet.XUnitV3Extensions`, namespace `Xunit`) until the underlying nondeterminism is fixed.

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> Generated by [Flaky Test Triage](https://github.com/dotnet/msbuild/actions/runs/30451703648) · sonnet46 · 150.7 AIC · ⌖ 5.46 AIC · ⊞ 14.7K · [◷](https://github.com/search?q=repo%3Adotnet%2Fmsbuild+is%3Aissue+%22gh-aw-workflow-call-id%3A+dotnet%2Fmsbuild%2Fflaky-test-detector.agent%22&type=issues)

Start with src/Tasks.UnitTests/CodeTaskFactoryTests.cs and the Microsoft.Build.UnitTests.CodeTaskFactoryTests.RedundantMSBuildReferences test. Reproduce it on the FullOnWindows Release leg targeting net472, then inspect the failing Assert.True result and the test's reference-handling setup. Done means the underlying nondeterminism is fixed and the test passes reliably across repeated builds.

Written by the indexing model from the issue text.