@UnstableApi
    public Endpoint withoutDefaultPort(SessionProtocol protocol) {
        requireNonNull(protocol, "protocol");
        return withoutDefaultPort(protocol.defaultPort());
    }
Returns a new host endpoint with the default port number of the specified {@link SessionProtocol}
removed.

@param protocol the {@link SessionProtocol} that will provide the default port number
@return the new endpoint without a port number if this endpoint had the same port number
        with the default port number provided by the specified {@link SessionProtocol}.
        {@code this} if this endpoint had a different port number than the default port number or
        this endpoint already does not have a port number.
core/src/main/java/com/linecorp/armeria/client/Endpoint.java