Update docstring for new filter

freqtrade/pairlist/VolumePairList.py

@@ -49,7 +49,7 @@ class VolumePairList(IPairList):
     def needstickers(self) -> bool:
         """
         Boolean property defining if tickers are necessary.
-        If no Pairlist requires tickers, an empty List is passed
+        If no Pairlist requires tickers, an empty Dict is passed
         as tickers argument to filter_pairlist
         """
         return True