Upgrade tf_logging.warn to tf_logging.warning.

PiperOrigin-RevId: 372315468
Change-Id: Ie73005cae1d6d700ef5c540462a375f528455128
diff --git a/tensorflow/python/saved_model/save.py b/tensorflow/python/saved_model/save.py
index e348c1b..9390a12 100644
--- a/tensorflow/python/saved_model/save.py
+++ b/tensorflow/python/saved_model/save.py
@@ -1219,7 +1219,7 @@
   meta_graph_def.object_graph_def.CopyFrom(object_graph_proto)
 
   if saved_object_metadata and raise_metadata_warning:
-    tf_logging.warn(
+    tf_logging.warning(
         'FOR KERAS USERS: The object that you are saving contains one or more '
         'Keras models or layers. If you are loading the SavedModel with '
         '`tf.keras.models.load_model`, continue reading (otherwise, you may '