Update trials.py

Hotfix

Author: RobertoDF

allensdk/brain_observatory/behavior/data_objects/trials/trials.py

@@ -275,7 +275,10 @@ def index(self) -> pd.Index:
 
     @property
     def change_time(self) -> pd.Series:
-        return self.data["change_time"]
+        if "change_time" in self.data:
+            return self.data["change_time"]
+        elif "change_time_no_display_delay" in self.data:
+            return self.data["change_time_no_display_delay"]
 
     @property
     def lick_times(self) -> pd.Series: