To be more consistent with K1, certain diagnostics should be reported
not on the whole properties' types, but on type arguments inside them.
Note that there is still a difference with K2 because K2 reports on a type argument
including its annotations, while K1 used KtTypeReference.typeElement.
IMO, K2 conveys the same or better meaning here, so I am willing to leave this
difference instead of providing PositioningStrategy.
#KT-53861 Fixed