fix for handling empty credentials

app.py

@@ -72,10 +72,10 @@ def start_experiment(
 
 
 def get_experiment(experiment_state):
-    api_key = experiment_state["api_key"]
-    workspace = experiment_state["workspace"]
-    project = experiment_state["project_name"]
-    experiment_name = experiment_state["experiment"]
+    api_key = experiment_state.get("api_key")
+    workspace = experiment_state.get("workspace")
+    project = experiment_state.get("project_name")
+    experiment_name = experiment_state.get("experiment")
 
     try:
         return comet_ml.API(api_key=api_key).get_experiment(