Azure Function coded with spring-cloud-function-adapter-azure SDK cannot return value of form of Mono/Flux.

We are using the spring-cloud-function-adapter-azure SDK to build our function.
We expect the return value to be in the form of Mono and Flux, but the we cannot return the corresponding value.

The code link provided by the official website: Getting started with Spring Cloud Function in Azure | Microsoft Docs
After checking the code provided by the official website, we found that only the return value in the HTTP response format was provided as follows:

```
public class HelloHandler extends FunctionInvoker {

@FunctionName("hello")
public HttpResponseMessage execute(
@HttpTrigger(name = "request", methods = {HttpMethod.GET, HttpMethod.POST}, authLevel = AuthorizationLevel.ANONYMOUS) HttpRequestMessage> request,
ExecutionContext context) {
User user = request.getBody()
.filter((u -> u.getName() != null))
.orElseGet(() -> new User(
request.getQueryParameters()
.getOrDefault("name", "world")));
context.getLogger().info("Greeting user name: " + user.getName());
return request
.createResponseBuilder(HttpStatus.OK)
.body(handleRequest(user, context))
.header("Content-Type", "application/json")
.build();
}}
```

I did not find the return form of Mono and Flux. The return format that we wanted is as follows:

```
public class HelloHandler extends FunctionInvoker> {

@FunctionName("hello")
public HttpResponseMessage execute(
@HttpTrigger(name = "request", methods = {HttpMethod.GET, HttpMethod.POST}, authLevel = AuthorizationLevel.ANONYMOUS) HttpRequestMessage> request,
ExecutionContext context) {
// ...
}
```

We want to know whether the return of Mono and Flux is supported on Azure, because the customer found that .NET can return the corresponding value, as follows:

```
[FunctionName("Httpxample")]
public static async Task Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HtppREquest req,
Iloogger log
)
```

Please confirm the feasibility of this request. Thank you very much for your help.

El issue menciona spring-cloud-function-adapter-azure y muestra los ejemplos de HelloHandler, pero no identifica ningún archivo del repositorio ni ninguna prueba. Empieza revisando el adaptador y la ruta de invocación de la función HTTP de Azure para determinar si se admiten los retornos de Mono y Flux. Done debe ser una respuesta clara sobre la viabilidad, con la ruta de implementación o documentación relevante identificada.

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