Validate BehaviorBase<T> and what is needed (if anything) beyond Behavior<T>

We probably want to file an issue about re-checking all this, as I know some of the original issues I believe were fixed in the underlying behaviors package, but I think we still do some extra logic here.

Probably a thing where when we can better test these and shore that up, we could try removing the intermediate class and see what happens or if anything breaks. (Assuming we have enough coverage)

_Originally posted by @michael-hawker in https://github.com/CommunityToolkit/Windows/pull/20#discussion_r1167170975_

Related Toolkit Discussion: https://github.com/CommunityToolkit/WindowsCommunityToolkit/issues/3856

with specifically more prior context and links here: https://github.com/CommunityToolkit/WindowsCommunityToolkit/issues/3856#issuecomment-801471909

Comienza con la Toolkit Discussion relacionada y el contexto previo enlazado; después compara BehaviorBase con Behavior e identifica qué lógica adicional permanece aquí. Establece una cobertura de pruebas suficiente antes de evaluar si se puede eliminar la clase intermedia sin romper el comportamiento.

Escrito por el modelo de indexación a partir del texto del issue.