Rely more on AnnotedTypes in CDI Extension again

[jungm]

For the related discussion see https://lists.apache.org/thread/3py3htgx0l4bd46tsd90l138xqy65s7t

@rmannibucau sorry it took me a bit to get back on this but please take a look if this is what you had in mind. I'm not really sure how I should read type hierarchy from AnnotatedTypes, all ways I found to do that lead through java.lang.reflect.* land