[DCR]: NuGet VS extensibility packages should suppress themselves from customer vsix

[zivkan]

NuGet Product(s) Affected

NuGet SDK

Current Behavior

If you create a VSIX project in VSIX, and build it, notice that none of the VS SDK assemblies are in the bin folder or in the vsix itself.

Now add a PackageReference to NuGet.VisualStudio and/or NuGet.VisualStudio.Contracts and build again. Now NuGet's assemblies are both in the bin folder and the vsix

Desired Behavior

Since NuGet.VisualStudio.dll and NuGet.VisualStudio.Contracts.dll have binding redirects and CodeBase in devenv.exe.config, plus the customer's extension would break if their extension used the copy from their own folder instead of the one NuGet itself uses. Hence these assemblies should not be included in the vsix.

Additional Context

The VS SDK appears to use an MSBuild item <SuppressFromVsix Include="nameof.dll" />