Use Combinatorial.MSTest for boolean DataRow tests in Microsoft.NET.Build.Tasks.Tests

[Evangelink]

Summary

Replaces full boolean cartesian-product [DataRow] sets with [CombinatorialData] in the Microsoft.NET.Build.Tasks.Tests project.

What changed

• 8 test methods across two files (GivenADependencyContextBuilder.cs, GivenAResolvePackageDependenciesTask.cs) had patterns like:

  [DataRow(true)]
  [DataRow(false)]
  public void SomeTest(bool flag) { ... }

  replaced with:

  [CombinatorialData]
  public void SomeTest(bool flag) { ... }

• The executed test cases are identical — [CombinatorialData] automatically generates true/false for each bool parameter.
• Microsoft.NET.Build.Tasks.Tests.csproj gains a new ItemGroup with:
  • <PackageReference Include="Combinatorial.MSTest" />
  • <Using Include="Combinatorial.MSTest" /> (global using, no per-file import needed)

Why

Full boolean [DataRow] enumerations are boilerplate that Combinatorial.MSTest handles automatically and more readably. This is part of a per-project series applying this pattern across the SDK test suite.

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