"Instantiating StoreFileTracker impl" INFO level logging is too chatty

<datetime> INFO [<threadname>] storefiletracker.StoreFileTrackerFactory: instantiating StoreFileTracker impl ....

This should be logged at DEBUG level as it is debug information. It is frequently printed in the logs and because it's the same impl every time (although in theory could be varied in table schema) there is no value for operators, it just consumes logging resources.