Add a CLI flag --show_secrets to clickhouse

Why it matters

This feature improves security and privacy by preventing sensitive data from being displayed unintentionally when using the clickhouse format command. Users can now control the visibility of sensitive information, reducing the risk of accidental exposure.

How to use it

When using the clickhouse format command, sensitive data is hidden by default. To display sensitive data, explicitly pass the --show_secrets flag in the command line.