Adds `to_redacted_sql` support for ClickHouse QueryBuilder

What does this MR do and why?

This MR implements the QueryLike interface for ClickHouse::Client which allows us to implement a common way of generating SQL queries. The ClickHouse::Client::Query class was added to support raw SQL queries.

• to_sql: the SQL query which will be sent to ClickHouse
• to_redacted_sql: where the SQL query is normalized and placeholder variables are replaced with $n values.

Additionally, a documentation page was added which gives an overview about how CH development is happening within GitLab.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #421403 (closed)