Rework @Configuration class that users may subclass to indicate whether or not they require proxying

[wilkinsona]

This is related to spring-projects/spring-session#1345.

It would be beneficial if @Configuration classes that are intended to be sub-classed by users could be annotated with @Configuration(proxyBeanMethods=false) to indicate that they do not require proxying. If there are configuration classes where proxying is required (due to inter-dependent @Bean methods) it would be beneficial if they were reworked so that proxying is no longer required.

[gregturn]

Thanks @wilkinsona. When we upgrade to Spring Framework 5.2, we'll be able to consider it.