Add a dummy argument deep to TargetEncoder.get_params() (rapidsai…

…#4601)

This is the continuation of PR rapidsai#4588 to resolve issue rapidsai#4574

Authors:
  - Jiwei Liu (https://github.com/daxiongshu)

Approvers:
  - Dante Gama Dessavre (https://github.com/dantegd)

URL: rapidsai#4601

python/cuml/preprocessing/TargetEncoder.py

@@ -451,7 +451,7 @@ def get_param_names(self):
             "n_folds", "smooth", "seed", "split_method",
         ]
 
-    def get_params(self):
+    def get_params(self, deep=False):
         """
         Returns a dict of all params owned by this class.
         """