Similar to $1307 Reactive function returns value rather then message.

[olegz]

Also, during composition, if reactive function is last, there is an issue with type conversion

@Bean
	public Function<Person, Person> uppercase() {
		return v -> {
			return new Person(v.getName().toUpperCase());
		};
	}
	
	@Bean
	public Function<Flux<String>, Flux<String>> concat() {
		return flux -> flux.map(v -> {
			return v + v;
		});
	}