Fix MySQL-related Settings in Dictionary Source and Named Collection

Why it matters

This update addresses issues where certain MySQL-specific configuration settings were not properly processed when using the MySQL dictionary source along with named collections. This ensures better compatibility and reliability when integrating MySQL dictionaries in ClickHouse.

How to use it

Users leveraging the MySQL dictionary source and named collections do not need to change their configurations. The fix is applied internally, improving the processing of MySQL-related settings automatically after upgrading to the version including this fix.