Automatically select DLL and XML files for API ref generation

[gewarren]

Automate these steps in the API ref generation process:

1. Get assemblies/XML files for core .NET libraries.

   • Download the https://www.nuget.org/packages/Microsoft.NETCore.App.Ref package. (Check the version first!)
   • Remove the façade DLLs listed in https://github.com/dotnet/runtime/blob/v7.0.0-preview.1.22076.8/src/libraries/shims/netfxreference.props.
   • Remove the non-source-of-truth XML documentation files. Usually just keep these:
     • System.Formats.Asn1.xml
     • System.Linq.AsyncEnumerable.xml
     • System.Net.ServerSentEvents.xml
   • Copy the assemblies (and XML files if using) into the /dotnet/ folder (clear it first if necessary).

2. Get assemblies/XML files for Windows Desktop libraries.

   • Download the https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Ref package. (Check the version first!)
   • Remove all the façade dlls except WindowsBase.dll (usually just Microsoft.VisualBasic.dll and System.Drawing.dll).
   • Remove the XML documentation files.
   • Copy everything into the /dotnet/windowsdesktop- folder (clear it first if necessary).
   • Copy System.Security.Cryptography.dll from /dotnet/ to /dotnet/dependencies/windowsdesktop- (overwrite old copy if necessary).

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Associated WorkItem - 537280