public Http1HeaderNaming http1HeaderNaming() {
        return get(HTTP1_HEADER_NAMING);
    }
Returns the {@link Http1HeaderNaming} which converts a lower-cased HTTP/2 header name into
another header name. This is useful when communicating with a legacy system that only supports
case-sensitive HTTP/1 headers.
core/src/main/java/com/linecorp/armeria/client/ClientFactoryOptions.java