code: public Response delete(String endpoint, Request params, File file) {
          return call(Method.DELETE, endpoint, params, file);
      }
docs: Performs a delete http call and writes the call and response information
  to the output file
  
  @param endpoint - the endpoint of the service under test
  @param params   - the parameters to be passed to the endpoint for the service
  call
  @param file     - an input file to be provided with the call
  @return Response: the response provided from the http call