call drop method on out_data

this should handle cases where out_data doesn't exist

Author: pattonw

src/volara_torch/blockwise/predict.py

@@ -112,7 +112,7 @@ def output_datasets(self) -> list[Dataset]:
     def drop_artifacts(self):
         for out_data in self.out_data:
             if out_data is not None:
-                rmtree(out_data.store)
+                out_data.drop()
 
     def init(self):
         self.init_out_array()