Spring BeanDefinitionDsl: get environment property in a nice way

With this PR I'd like to open a discussion about a way to easily access Environment properties in BeanDefinitionDsl.

Comment From: krzykrucz

I am not sure as to the name of the method (props), because this method can be used not only to fetch single properties, but also whole configuration trees (as an alternative to a @ConfigurationProperties mechanism)

Comment From: krzykrucz

@sdeleuze Could you have a look, please?

Comment From: krzykrucz

@jhoeller @sdeleuze Would it be possible to speed up a bit this PR and https://github.com/spring-projects/spring-framework/pull/25097 ? 🙂

Comment From: sdeleuze

Hey, sorry for the delay. You can already access pretty easily to the environment via env["foo"], env.getProperty<Foo>("foo") and env.getRequiredProperty<Foo>("foo") so not need for additional capabilities IMO.