more fixes

app.py

@@ -48,7 +48,7 @@ async def initialize_data():
 
 def update_sources_list(question_option, source_finder_id, run_id: str, baseline_ranker_id: str, evt: gr.EventData = None):
     global previous_run_id
-    if evt.target.elem_id == "run_id_dropdown":
+    if evt and evt.target.elem_id == "run_id_dropdown":
         if type(run_id) == list or run_id == previous_run_id:
             return gr.skip(), gr.skip(), gr.skip(), gr.skip()