Add product name to client useragnet

To have a better differentiation in the ClickHouse `system.query_log`, we need to append to the ClickHouse Client the Flink connector version & Flink version. see: https://github.com/ClickHouse/clickhouse-kafka-connect/blob/main/src/main/java/com/clickhouse/kafka/connect/sink/db/helper/ClickHouseHelperClient.java#L85 