Revert ensemble.py to release/v_1.5.0 version

Author: shuds13

libensemble/ensemble.py

@@ -578,11 +578,14 @@ def save_output(self, basename: str, append_attrs: bool = True):
         Format: ``<basename>_results_History_length=<length>_evals=<Completed evals>_ranks=<nworkers>``
         """
         if self.is_manager:
-            save_libE_output(
-                self.H,
-                self.persis_info,
-                basename,
-                self.nworkers,
-                dest_path=self.libE_specs.workflow_dir_path,
-                append_attrs=append_attrs,
-            )
+            if self._get_option("libE_specs", "workflow_dir_path"):
+                save_libE_output(
+                    self.H,
+                    self.persis_info,
+                    basename,
+                    self.nworkers,
+                    dest_path=self.libE_specs.workflow_dir_path,
+                    append_attrs=append_attrs,
+                )
+            else:
+                save_libE_output(self.H, self.persis_info, basename, self.nworkers, append_attrs=append_attrs)