private void http1Codec(ChannelPipeline pipeline) {
        pipeline.replace("codec_placeholder", HTTP_CODEC_HANDLER_NAME, createHttpServerCodec());
    }
Use {@link #Http2SslChannelInitializer(String, ChannelConfig, ChannelConfig, ChannelGroup)} instead.
zuul-core/src/main/java/com/netflix/zuul/netty/server/http2/Http2SslChannelInitializer.java