Use Combinatorial.MSTest for boolean DataRow tests in TemplateEngine unit tests

[Evangelink]

Summary

Replaces full boolean cartesian-product [DataRow] sets with [CombinatorialData] (from the Combinatorial.MSTest package) in the TemplateEngine test subprojects.

What changed

• Microsoft.TemplateEngine.Core.UnitTests – 2 methods converted:
  • VerifyWhitespaceHandlerConsumeWholeLine (8 DataRows → CombinatorialData)
  • VerifyWhitespaceHandlerTrim (4 DataRows → CombinatorialData)
• Microsoft.TemplateEngine.TemplateLocalizer.Core.UnitTests – 2 methods converted:
  • UnchangedFileShouldntBeOverwritten (2 DataRows → CombinatorialData)
  • BomPreambleIsPreserved (2 DataRows → CombinatorialData)

Both .csproj files receive a new ItemGroup with:

<PackageReference Include="Combinatorial.MSTest" />
<Using Include="Combinatorial.MSTest" />

Behaviour

Identical test cases are executed — [CombinatorialData] generates the same full boolean product as the explicit [DataRow] list, just without the boilerplate.

Series

This is part of a per-project series replacing redundant boolean [DataRow] combinations with [CombinatorialData] across the SDK test suite.

Co-authored-by: Copilot 223556219+Copilot@users.noreply.github.com

[github-actions]

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