Revert changes made to run history assertion in base taks #1257

Author: ravinkohli

autoPyTorch/api/base_task.py

@@ -1254,7 +1254,8 @@ def get_incumbent_results(
         Returns:
 
         """
-        if self.run_history is not None or self.run_history.empty():
+        assert self.run_history is not None, "No Run History found, search has not been called."
+        if self.run_history.empty():
             raise ValueError("Run History is empty. Something went wrong, "
                              "smac was not able to fit any model?")