[#41] log: Log storage operations in only in Debug

They are mostly useless unless we need to _debug_ a specific issue.
The amount of logs we produce is too big.

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

pkg/local_object_storage/internal/log/log.go

@@ -10,7 +10,7 @@ const headMsg = "local object storage operation"
 
 // Write writes message about storage engine's operation to logger.
 func Write(logger *logger.Logger, fields ...zap.Field) {
-	logger.Info(headMsg, fields...)
+	logger.Debug(headMsg, fields...)
 }
 
 // AddressField returns logger's field for object address.