Spring Consistent ROLE_INFRASTRUCTURE declarations for internal configuration classes

As indicated by #24508, we inconsistently use @Role(BeanDefinition.ROLE_INFRASTRUCTURE) at the class level of our internal configuration classes: not only affecting ProxyTransactionManagementConfiguration but also AspectJ configuration variants as well as LoadTimeWeavingConfiguration and MBeanExportConfiguration. We should sort this out for good and also backport it, even for cases where it does not cause a regression in terms of warn log entries.