Use Consistent Default Paths for ClickHouse Keeper Symlink and Executable

Why it matters

This change ensures consistency in the default file system paths used by clickhouse-keeper, regardless of whether it is run via the symlink or directly as an executable. It simplifies management by avoiding path discrepancies and potential configuration errors.

How to use it

Users do not need to take any specific action. By using either the clickhouse-keeper symlink or executable, the same default paths for configuration and data will be applied automatically.