Support for application/cloudevents+json

[murari-goswami]

I am using AsyncAPI in conjunction with cloudevents. For this the default content type as for media I chose as "application/cloudevents+json" as per the official cloudevent spec https://github.com/cloudevents/spec/blob/main/cloudevents/formats/json-format.md. Accordingly, I use defaultContentType: application/cloudevents+json in the AsyncAPI specification. All good until here. Later in the process when we generate markdown from the api spec, the AsyncAPI markdown generator puts hyperlink for "application/cloudevents+json" as https://www.iana.org/assignments/media-types/application/cloudevents+json. Where as iana has no valid "application/cloudevents+json" as media type yet. Can anyone help me here how can "application/cloudevents+json" is registered in iana. Alternatively, can the hyperlink generator from markdown converter be suppressed for this broken link ?