Merge branch 'lukas_issue369_bug_crash-when-no-competitor-is-provided' into 'develop'

Lukas issue369 bug crash when no competitor is provided

See merge request !404

mlair/run_modules/experiment_setup.py

@@ -389,7 +389,7 @@ class ExperimentSetup(RunEnvironment):
         self._set_param("neighbors", ["DEBW030"])  # TODO: just for testing
 
         # set competitors
-        if model_display_name is not None and model_display_name in competitors:
+        if model_display_name is not None and competitors is not None and model_display_name in competitors:
             raise IndexError(f"Given model_display_name {model_display_name} is also present in the competitors "
                              f"variable {competitors}. To assure a proper workflow it is required to have unique names "
                              f"for each model and competitor. Please use a different model display name or competitor.")