Skip smollm3 tests in tests-bwd (#821)

## Summary
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Skip smollm3 tests in tests-bwd as it is only available for
transformers>=4.53.0. This will help fix tests-bwd on nvidia.
 
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## Details
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## Testing Done
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Author: vaibhavjindal

test/transformers/test_monkey_patch.py

@@ -1634,6 +1634,7 @@ def test_apply_liger_kernel_to_instance_for_glm4():
             pytest.fail(f"An exception occured in extra_expr: {type(e).__name__} - {e}")
 
 
+@pytest.mark.skipif(not is_smollm3_available(), reason="smollm3 module not available")
 def test_apply_liger_kernel_to_instance_for_smollm3():
     # Ensure any monkey patching is cleaned up for subsequent tests
     with patch("transformers.models.smollm3.modeling_smollm3"):