[mypyc] Reject calling a property through class object

[rheard]

Follow-up to #22139, from this review comment.

mypy types C.prop as the property's getter, so it accepts C.prop(obj). At runtime, C.prop is the property object (a getset descriptor for a native class), and calling it raises TypeError: 'property' object is not callable. For a native class, mypyc compiled C.prop(obj) as a direct call to the getter, so it returned obj.prop instead of raising. The same happened with inherited, read-write and trait properties, and with cls.prop(obj) in a classmethod of a class with no subclasses. If the getter was an abstract trait property with an empty body, the process aborted (Fatal Python error: Aborted).

mypyc now reports an error for these calls, like the existing error for accessing an instance attribute through a class object:

error: Cannot call property "prop" through class object

#18969 would make mypy report these calls ("property" not callable) in code that it type checks, but mypyc still needs its own check.