Update parameters in get_params

The two parameters `validation_fraction` and `early_stopping_rounds` have been added to the `params` dictionary.

Author: CoRiis

ngboost/ngboost.py

@@ -512,6 +512,8 @@ def get_params(self, deep=True):
             "col_sample": self.col_sample,
             "verbose": self.verbose,
             "random_state": self.random_state,
+            "validation_fraction": self.validation_fraction,
+            "early_stopping_rounds": self.early_stopping_rounds,
         }
 
         return params