Logging level about the selected parts

Why it matters

The previous logging level for parts selected for merging was set incorrectly to Information, which could clutter logs or misrepresent the importance of the message. Adjusting the logging level improves log clarity and helps users better interpret merging operations.

How to use it

This change is internal and applied automatically upon updating to the new ClickHouse version. No user action is needed to benefit from the corrected logging behavior.