public void buildElasticConnectionPool(final Builder builder) {
        // about the args, please see https://projectreactor.io/docs/netty/release/reference/index.html#_connection_pool_2
        builder.maxConnections(Integer.MAX_VALUE)
                .pendingAcquireTimeout(Duration.ofMillis(0))
                .pendingAcquireMaxCount(-1);
    }
build elastic connection provider pool.

@param builder connection provider builder
shenyu-spring-boot-starter/shenyu-spring-boot-starter-plugin/shenyu-spring-boot-starter-plugin-httpclient/src/main/java/org/apache/shenyu/springboot/starter/plugin/httpclient/HttpClientFactory.java