In some cases we transform flexible type into non-flexible during
enhancement, but don't add `@EnhancedNullability` attribute to them,
which breaks consistency with K1 on IR level
This commit fixes it
^KT-65302
A class can inherit two declarations that are compatible from the
overridability standpoint and are therefore combined to a non-trivial
intersection.
At the same time, the class can declare a member declaration that
only overrides one of the intersection's members.
In this case, we break up the intersection and only add the overridden
parts to the declared member's direct overridden list.
If the class doesn't override the intersection, it exists as
intersection override, like before.
#KT-65487 Fixed
Alexander Udalov