[#585] fstree: Return logical error if object deleted

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/blobstor/fstree/fstree.go

@@ -429,6 +429,9 @@ func (t *FSTree) Get(ctx context.Context, prm common.GetPrm) (common.GetRes, err
 
 		data, err = os.ReadFile(p)
 		if err != nil {
+			if os.IsNotExist(err) {
+				return common.GetRes{}, logicerr.Wrap(new(apistatus.ObjectNotFound))
+			}
 			return common.GetRes{}, err
 		}
 	}