Resolve "release v1.4.0"

Closes #317 (closed)

mlair/run_modules/post_processing.py

@@ -306,7 +306,7 @@ class PostProcessing(RunEnvironment):
         try:
             if ("filter" in self.test_data[0].get_X(as_numpy=False)[0].coords) and (
                     "PlotSeparationOfScales" in plot_list):
-                filter_dim = self.data_store.get("filter_dim", None)
+                filter_dim = self.data_store.get_default("filter_dim", None)
                 PlotSeparationOfScales(self.test_data, plot_folder=self.plot_path, time_dim=time_dim,
                                        window_dim=window_dim, target_dim=target_dim, **{"filter_dim": filter_dim})
         except Exception as e: