openapi RouterBuilder support for Upload via Multipart Request

Hi,

When migrating to 4.6.6, I encountered that RouterBuilder does not handle Multipart Requests, but, it is the way, if you want to upload files, with other information together.

Sorry, it is the io.vertx.openapi.contract.impl package, which doesn't support Multipart Requests

At the moment we only support application/json [1]. We would need to implement a new multipart/form-data BodyTransformer, like the ApplicationJsonTransformer [2].

I have a lot of other TODOs on my list, but if you want to help / contribute, we could work on it.

[1]

vertx-openapi/src/main/java/io/vertx/openapi/contract/MediaType.java

Line 34 in d0be35d

    
           List<String> SUPPORTED_MEDIA_TYPES = Arrays.asList(APPLICATION_JSON, APPLICATION_JSON_UTF8);

[2] https://github.com/eclipse-vertx/vertx-openapi/blob/main/src/main/java/io/vertx/openapi/validation/transformer/ApplicationJsonTransformer.java