chore: add typing for hyperopt-pickle-magic

Author: xmatthias

freqtrade/optimize/hyperopt/hyperopt_optimizer.py

@@ -114,7 +114,7 @@ def prepare_hyperopt(self) -> None:
     def get_strategy_name(self) -> str:
         return self.backtesting.strategy.get_strategy_name()
 
-    def hyperopt_pickle_magic(self, bases) -> None:
+    def hyperopt_pickle_magic(self, bases: tuple[type, ...]) -> None:
         """
         Hyperopt magic to allow strategy inheritance across files.
         For this to properly work, we need to register the module of the imported class