Triggers the execution of the handler in order to produce an HTTP response.

This method will be called by the Marten server when it comes to produce an HTTP response once a handler has been identified for the considered route. This method will execute the handler method associated with the considered HTTP method (eg. #get for the GET method) in order to return the final HTTP response. A 405 response will be returned if the considered HTTP method is not allowed. The #dispatch method can also be overridden on a per-handler basis in order to implement any other arbitrary logics if necessary.