Changes to Generate dataset metadata

removed the media type application/json from the request body

added the media type multipart/form-data to the request body

removed the media type multipart/form-data from the request body

added the media type application/json to the request body

added the new optional request property content_url

added the new optional request property encoding_format

added the new optional request property filename

added the new optional request property sha256

removed the media type application/json from the request body

added the media type multipart/form-data to the request body