Fix 9150 --- #i nuget on desktop witout net48 ref assemblies fails. (#10114)

Author: KevinRansom

src/fsharp/FSharp.DependencyManager.Nuget/FSharp.DependencyManager.ProjectFile.fs

@@ -144,6 +144,10 @@ $(POUND_R)
     <FSharpCoreImplicitPackageVersion Condition="'$(FSharpCoreImplicitPackageVersion)' == '{{FSharpCorePreviewPackageVersion}}'">4.7.1-*</FSharpCoreImplicitPackageVersion>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include='Microsoft.NETFramework.ReferenceAssemblies' Version='1.0.0' Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'"/>
+  </ItemGroup>
+
 $(PACKAGEREFERENCES)
 
   <Target Name="ComputePackageRootsForInteractivePackageManagement"

src/fsharp/FSharp.DependencyManager.Nuget/FSharp.DependencyManager.fs

@@ -69,6 +69,7 @@ module FSharpDependencyManager =
                         validatePackageName v "FSharp.Core"
                     validatePackageName v "System.ValueTuple"
                     validatePackageName v "NETStandard.Library"
+                    validatePackageName v "Microsoft.NETFramework.ReferenceAssemblies"
                     Some { current with Include = v }
                 let setVersion v = Some { current with Version = v }
                 match opt with