Fix batch.py

Author: itearsl

bench.py

@@ -505,7 +505,8 @@ def gen_basic_dict(library, algorithm, stage, params, data, alg_instance=None,
             alg_instance_params = dict(alg_instance.get_params())
             if ('handle' in alg_instance_params
                     and 'cuml' in str(alg_instance_params['handle'])):
-                alg_instance_params['dtype'] = str(alg_instance_params['dtype'])
+                    if 'min_samples_split' in alg_instance_params:
+                        alg_instance_params['dtype'] = str(alg_instance_params['dtype'])
         result['algorithm_parameters'].update(alg_instance_params)
     if alg_params is not None:
         result['algorithm_parameters'].update(alg_params)