Restore CallerMemberName example

[RexJaeschke]

Jon, this addresses your comment.

[KalleOlaviNiemitalo]

Filed #1549. But also:

using System;
using System.Runtime.CompilerServices;

public class MAttribute : Attribute {
    public MAttribute(
        [CallerMemberName]string? name = null) {
    }
}

class C { 
    void Fun1() {
        void Fun2<[M]T>(){}
    }
}

SharpLab shows this being lowered to void Fun2<[M("Fun2")]T>(){} but the draft seems to require void Fun2<[M("Fun1")]T>(){} because Fun2 as a local function is not a function member. Now is that a compiler bug or a spec bug?