Prior to this commit, methods in a @ControllerAdvice bean were
registered and invoked twice if the advice was a scoped bean (e.g.,
request or session scoped). In other words, both the proxy bean and the
target bean were wrapped in ControllerAdviceBean instances.

This commit fixes this bug by modifying the findAnnotatedBeans() method
in ControllerAdviceBean so that it filters out targets of scoped
proxies.

Closes gh-24017