Deactivate mutations_finalizing_task before shutdown to prevent TABLE_IS_READ_ONLY errors

Why it matters

This feature addresses the issue where the mutations_finalizing_task runs during shutdown, causing harmless but confusing TABLE_IS_READ_ONLY errors. By deactivating this task before shutdown, it ensures a cleaner shutdown process without unnecessary error messages, improving user experience and log clarity.

How to use it

The mutations_finalizing_task is automatically deactivated before the server shutdown sequence. Users do not need to manually enable this feature; it is part of the improved shutdown procedure.