Fix failed introspection for duplicated properties

[davidsonnabend]

Initial fix for #12262.

I’m curious if you think this is the best path forward or if you’d prefer a different implementation.

Please let me know if anything can be improved or needs to be solved differently.

[dstepanov]

I think the correct way is to fix it on AstBeanPropertiesUtils#resolveBeanProperties. Please also check setting/getting value works.

[davidsonnabend]

I think I found the root cause. AstBeanPropertiesUtils isn't involved for this specific case.

The problem is that KSPropertyDeclaration::findOverridee() always returns the first declared interface. Thus, the check for overridden properties only works for the first interface (A::foo). The same property of the second interface (B::foo) is considered as a new property. This results in the list of duplicated properties and the described bug.