Microsoft.Extensions.DependencyInjection.Specification.Tests are included in .NET API documentation

[jeffhandley]

Describe the issue or suggestion

Example URL: https://learn.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.specification?view=net-9.0-pp

It's possible other test assemblies/APIs from dotnet/extensions are also included in the API docs.

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Associated WorkItem - 486268

[gewarren]

@jeffhandley The script that identifies which NuGet packages to pull docs from looks for packages owned by dotnetframework or aspnet and then applies a filter. The list of packages that populated the .NET 9 package-provided docs is here. Can you take a look and let me know if there are others to exclude?