@Override
    public ExchangeType exchangeType(RoutingContext routingContext) {
        return ExchangeType.UNARY;
    }
{@link HttpService} to handle a {@link WebOperation}. Mostly inspired by reactive implementation in
{@link AbstractWebFluxEndpointHandlerMapping}.
spring/boot3-actuator-autoconfigure/src/main/java/com/linecorp/armeria/spring/actuate/WebOperationService.java