in src/Microsoft.NuGet.Build.Tasks/ResolveNuGetPackageAssets.cs [797:800]
private string GetTargetMonikerWithOptionalRuntimeIdentifier(ITaskItem preferredTargetMoniker, bool needsRuntimeIdentifier)
{
return needsRuntimeIdentifier ? preferredTargetMoniker.ItemSpec + "/" + RuntimeIdentifier : preferredTargetMoniker.ItemSpec;
}