Support of multiple outputs on function composition

[raycheung]

Describe the issue I'm trying to define the function definition as supplierA|functionB, while they have the following signatures:

@Bean
public Supplier<Flux<Map<String, Object>>> supplierA() { ... }

@Bean
public Function<Flux<Map<String, Object>>, Tuple2<Flux<Map<String, Object>>, Flux<Map<String, Object>>>> functionB() { ... }

Turns out, the composed function would try to output Flux<Tuple2<Flux<Map<String, Object>>, Flux<Map<String, Object>>>> in supplierAfunctionB-out-0, instead of two Flux<Map<String, Object>> in supplierAfunctionB-out-0 and supplierAfunctionB-out-1.

To Reproduce As above.

Version of the framework 3.0.4.RELEASE

Expected behavior Somehow allow configuring the multiple outputs of the composed function.