Fixed extra emitted pop when consuming IL types with init properties

[TIHan]

C#:

namespace ClassLibrary1
{
    public record Test
    {
        public int X { get; init; }
    }
}

F#:

open ClassLibrary1
open System.Runtime.CompilerServices

[<MethodImpl(MethodImplOptions.NoInlining)>]
let test() =
    Test(X = 1)

[<EntryPoint>]
let main argv =
    test() |> ignore
    0

The emitted IL from the F# code:

.method public static class [ClassLibrary1]ClassLibrary1.Test 
        test() cil managed noinlining
{
  // Code size       16 (0x10)
  .maxstack  4
  .locals init (class [ClassLibrary1]ClassLibrary1.Test V_0)
  IL_0000:  newobj     instance void [ClassLibrary1]ClassLibrary1.Test::.ctor()
  IL_0005:  stloc.0
  IL_0006:  ldloc.0
  IL_0007:  ldc.i4.1
  IL_0008:  callvirt   instance void modreq([System.Runtime]System.Runtime.CompilerServices.IsExternalInit) [ClassLibrary1]ClassLibrary1.Test::set_X(int32)
  IL_000d:  pop
  IL_000e:  ldloc.0
  IL_000f:  ret
} // end of method Program::test

Notice the IL_000d: pop - there should not be one here as there is nothing to pop and results in invalid IL and causes the runtime to throw.

The PR should fix this by stripping away ILType.Modified IL types when checking for a return type on an IL call.