Replace persist_models with persist call due to API deprecation (#164)

Author: tonyhoo

src/autogluon/cloud/scripts/sagemaker_scripts/tabular_serve.py

@@ -32,7 +32,7 @@ def _save_image_and_update_dataframe_column(bytes):
 def model_fn(model_dir):
     """loads model from previously saved artifact"""
     model = TabularPredictor.load(model_dir)
-    model.persist_models()
+    model.persist()
     globals()["column_names"] = model.original_features
 
     return model

tests/unittests/tabular/test_tabular.py

@@ -68,5 +68,5 @@ def test_tabular_tabular_text_image(test_helper, framework_version):
         local_predictor = cloud_predictor.to_local_predictor(
             require_version_match=False, require_py_version_match=False
         )
-        models = local_predictor.get_model_names()
+        models = local_predictor.model_names()
         assert "ImagePredictor" in models