Updated kraken._get_funding_fee docstring with notification that it won't work in the bot yet

freqtrade/exchange/kraken.py

@@ -165,6 +165,10 @@ class Kraken(Exchange):
         time_in_ratio: Optional[float] = None
     ) -> float:
         """
+            # ! This method will always error when run by Freqtrade because time_in_ratio is never
+            # ! passed to _get_funding_fee. For kraken futures to work in dry run and backtesting
+            # ! functionality must be added that passes the parameter time_in_ratio to
+            # ! _get_funding_fee when using Kraken
             Calculates a single funding fee
             :param size: contract size * number of contracts
             :param mark_price: The price of the asset that the contract is based off of