[Feature] Add JSON body items to http.request

[Julian-Louis]

Describe the feature you'd like

Hello 👋
When setting DD_TRACE_HTTP_POST_DATA_PARAM_ALLOWED to *
Only application/x-www-form-urlencoded requests seems to add post data to http.request.

It could be nice to also have application/json requests adding post data to http.request.

Don't hesitate if you have any questions,
Thank you,

Is your feature request related to a problem?

No response

Describe alternatives you've considered

No response

Additional context

No response