Possible bug: TypedReference* (and other restricted types) don't generate Warning CS8500

[hamarb123]

When taking pointers to any managed type (classes, ref structs, and structs with object members), it is supposed to generate CS8500:

These restricted types (TypedReference, ArgIterator, RuntimeArgumentHandle) are managed types and thus should generate the above warning.

Also, according to https://github.com/dotnet/csharplang/blob/main/proposals/csharp-11.0/low-level-struct-improvements.md#sunset-restricted-types, in the future these types may be viewed as ref structs, therefore they should give the warning now so users don't start randomly getting warnings: