Spring Explore if AbstractEntityManagerFactoryBean proxy hints can be inferred automatically

As a follow-up of #29138, let see if we can infer the EntityManagerFactoryInfo and EntityManagerProxy proxies created via AbstractEntityManagerFactoryBean infrastructure like in #29097 instead of creating related hints.

See related comment from @jhoeller here.

Comment From: sdeleuze

After a second thought and discussing with @jhoeller, we may be fine with our current arrangement of explicit hints here.