public static ClientBuilder builder(String scheme, EndpointGroup endpointGroup) {
        return builder(Scheme.parse(requireNonNull(scheme, "scheme")), endpointGroup);
    }
Returns a new {@link ClientBuilder} that builds the client that connects to the specified
{@link EndpointGroup} with the specified {@code scheme}.

@throws IllegalArgumentException if the {@code scheme} is invalid.
core/src/main/java/com/linecorp/armeria/client/Clients.java