code: public static Tag outcome(ServerWebExchange exchange) {
  		HttpStatus status = exchange.getResponse().getStatusCode();
  		if (status != null) {
  			if (status.is1xxInformational()) {
  				return OUTCOME_INFORMATIONAL;
  			}
  			if (status.is2xxSuccessful()) {
  				return OUTCOME_SUCCESS;
  			}
  			if (status.is3xxRedirection()) {
  				return OUTCOME_REDIRECTION;
  			}
  			if (status.is4xxClientError()) {
  				return OUTCOME_CLIENT_ERROR;
  			}
  			return OUTCOME_SERVER_ERROR;
  		}
  		return OUTCOME_UNKNOWN;
  	}
docs: Creates an {@code outcome} tag based on the response status of the given
  {@code exchange}.
  @param exchange the exchange
  @return the outcome tag derived from the response status
  @since 2.1.0