Issue with v2 endpoint of Rest Producer API

[21Priyanshu]

Issue Description

While using v2 endpoint of event streams Rest Producer API need to add 'schema' field in the request body though 'schema' is not mentioned as required field in the document related to reference of v2 endpoint producer API.

Getting this as response when not adding schema field in request body

**{
    "trace": "70334b86-a33f-4c23-a97a-b63ba6b9bbe9",
    "error": {
        "code": "missing_schema",
        "message": "Error parsing JSON request body: 'schema' field is required in 'value' object",
        "more_info": "https://cloud.ibm.com/apidocs/event-streams/restproducer",
        "target": {
            "type": "field",
            "name": "schema"
        }
    }
}**