Fixed a bug where if the architecture had entirely failed and not generated a response the whole load of TestGroups would crash. Need to fix the root cause of the failure to generate a response, but also should be caught gracefully here in any event.

src/testing.py

@@ -82,7 +82,10 @@ class ArchitectureRequestRecord:
     @classmethod
     def from_dict(cls, test: Dict) -> ArchitectureRequestRecord:
         arch = test['architecture']
-        response_len = len(test['request']['response_evolution'][-1])
+        if len(test['request']['response_evolution']) == 0:
+            response_len = 0
+        else:
+            response_len = len(test['request']['response_evolution'][-1])
         start = test['trace']['steps'][0]['start_ms']
         end = test['trace']['steps'][-1]['end_ms']
         elapsed = end - start