Revise dynamic bean registrations with the `IntegrationFlowContext`

[artembilan]

More info on StackOverflow: https://stackoverflow.com/questions/78933787/why-does-spring-not-clean-up-integrationflows-for-a-dynamic-tcp-client.

Apparently there is a memory leak when we remove bean definitions and the cache for their merged bean definition is not clear due to: spring-projects/spring-framework#23336.

The problem has a big impact when random bean names are used for the IntegrationFlowContext interaction.

Need to look into a way to deal with a SingletonBeanRegistry.registerSingleton() instead of a BeanDefinitionRegistry.registerBeanDefinition().