Let kagglehub select latest version (keras-team#1342)

This is a newly minted feature in kagglehub.

We should probably add a unit test for this, but probably after our
models are actually uploaded the hub.

keras_nlp/utils/preset_utils.py

@@ -40,7 +40,7 @@ def get_file(preset, path):
         # Insert the kaggle framework into the handle.
         if len(segments) == 3:
             org, model, variant = segments
-            kaggle_handle = f"{org}/{model}/keras/{variant}/1"
+            kaggle_handle = f"{org}/{model}/keras/{variant}"
         elif len(segments) == 4:
             org, model, variant, version = segments
             kaggle_handle = f"{org}/{model}/keras/{variant}/{version}"