Open types can exist as entries in interface map (#55372)
* Open types can exist as entries in interface map
- While invalid via the ECMA spec, the runtime currently represents a type explicitly instantiated over its own generic type parameters via the open type MethodTable
- This is not strictly correct, as per the spec, these should be represented via an instantiated type, but changing that detail at this time is considered highly risky
- This conflicts with the perf optimization around partialy interface loading which uses the open type of an interface to represent a type instantiated in the curiously recurring fashion.
- The fix is to detect types instantiated over generic variables, and make them ineligible for the optimization, and to detect those cases where the optimization is ineligible, and revert back to the non-optimized behavior
Fixes #55323