public static void setUnsupported(SocketAddress remoteAddress, SessionProtocol protocol) {
        requireNonNull(protocol, "protocol");
        final String key = key(remoteAddress);
        final CacheEntry e = getOrCreate(key);

        if (e.addUnsupported(protocol)) {
            logger.debug("Updated: '{}' does not support {}", key, e);
        }
    }
Updates the cache with the information that the specified {@code remoteAddress} does not support
the specified {@link SessionProtocol}.
core/src/main/java/com/linecorp/armeria/client/SessionProtocolNegotiationCache.java