@Override
        public void connectionOpen(SessionProtocol protocol, InetSocketAddress remoteAddr,
                                   InetSocketAddress localAddr, AttributeMap attrs) throws Exception {
            final ConnectionPoolListener connectionPoolListener =
                    HttpClientMaxConcurrentStreamTest.this.connectionPoolListener;
            if (connectionPoolListener != null) {
                connectionPoolListener.connectionOpen(protocol, remoteAddr, localAddr, attrs);
            }
        }
Makes sure Armeria HTTP client respects {@code MAX_CONCURRENT_STREAMS} HTTP/2 setting.
core/src/test/java/com/linecorp/armeria/client/HttpClientMaxConcurrentStreamTest.java