Honor rest signal template method return type

On some situations it is useful to overwrite rest templates, for instance a spring app that uses WebFlux framework, then signal template method could look like the following:

public Mono<$Type$Output> signal(@PathVariable("id") final String id, final @RequestBody(required = false) $signalType$ data) {

  return Mono.fromCallable(() ->

    ...

  );

}

but right now ProcessResourceGenerator class uses fixed output type derived from modelfqcn rather than cloned.getType()