fix call

Author: Christian-B

spynnaker/pyNN/spinnaker.py

@@ -402,7 +402,7 @@ def _execute_graph_provenance(self) -> None:
             if timer.skip_if_cfg_false("Reports",
                                        "read_graph_provenance_data"):
                 return
-            for partition in self._data_writer._iterate_partitions():
+            for partition in self._data_writer.iterate_partitions():
                 for edge in partition.edges:
                     if isinstance(edge, ProjectionApplicationEdge):
                         edge.get_local_provenance_data()