Stop Reporting Expected Zookeeper "Node Exists" Exceptions

Why it matters

This feature addresses the issue where expected Zookeeper "Node exists" exceptions were unnecessarily logged in the system.errors table, causing confusion and noise. By suppressing these expected exceptions, it improves the clarity and relevance of error reporting for users monitoring ClickHouse operations involving Zookeeper.

How to use it

This improvement is applied automatically in the new version of ClickHouse, requiring no configuration from users. Once upgraded, expected Zookeeper "Node exists" exceptions will no longer appear in the system.errors table.