* Make Iterable Map constructor argument optional
Fixes#37779
* Change Map constructor in iterable to accept both null and undefined.
According to the spec (https://tc39.es/ecma262/#sec-map-iterable), the sole argument passed to Map is allowed to be null or undefined.
* Changed Map constructor to ensure new Map() still types as Map<any, any>.
* Add map constructor test.
This proves that the previous commit fixes#37779, as well as that new Map() still types as Map<any, any>.
* Update baseline.
Co-authored-by: Jared Neil <jaredneil@lucidchart.com>
Pimm "de Chinchilla" HogelingandJared Neil