static WebClient of(String uri) {
        return builder(uri).build();
    }
Returns a new {@link WebClient} that connects to the specified {@code uri} using the default options.

@param uri the URI of the server endpoint

@throws IllegalArgumentException if the {@code uri} is not valid or its scheme is not one of the values
                                 in {@link SessionProtocol#httpValues()} or
                                 {@link SessionProtocol#httpsValues()}.
core/src/main/java/com/linecorp/armeria/client/WebClient.java