Update python-package/lightgbm/sklearn.py

Co-authored-by: Nikita Titov <[email protected]>

python-package/lightgbm/sklearn.py

@@ -1314,7 +1314,7 @@ def feature_names_in_(self) -> None:
 class LGBMRegressor(_LGBMRegressorBase, LGBMModel):
     """LightGBM regressor."""
 
-    def __init__(self, **kwargs: Any):
+    def __init__(self, **kwargs: Any) -> None:
         super().__init__(**kwargs)
 
     __init__.__doc__ = LGBMModel.__init__.__doc__