Remove IVT to FSharp.Build (#6970)

I'm feeling spicy, so I'm doing this with GitHub's web UI.

Author: cartermp

src/fsharp/FSharp.Compiler.Private/FSharp.Compiler.Private.fsproj

@@ -40,7 +40,6 @@
 
   <ItemGroup>
     <InternalsVisibleTo Include="fsc" />
-    <InternalsVisibleTo Include="FSharp.Build" />
     <InternalsVisibleTo Include="fsi" />
     <InternalsVisibleTo Include="fsiAnyCpu" />
     <InternalsVisibleTo Include="FSharp.LanguageService" />