Remove [Experimental] from the "Refreshable Materialized View" as it is now production ready

[jotosoares]

On this page: https://clickhouse.com/docs/en/sql-reference/statements/create/view#refreshable-materialized-view, the title suggests that Refreshable Materialized Views are still an experimental feature. However, this blog post https://clickhouse.com/blog/clickhouse-release-24-10#refreshable-materialized-views-production-ready states otherwise.

For this reason, I believe the title should be updated to remove the word "Experimental" .