Fix coreml

[grimoire]

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Modification

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Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
2. The modification is covered by complete unit tests. If not, please add more unit tests to ensure the correctness.
3. If the modification has a dependency on downstream projects of a newer version, this PR should be tested with all supported versions of downstream projects.
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[irexyc]

Please fix the lint error.

It's fine to fix #1652

For some model like resnet18_8xb32_in1k.py, we can only deploy the model with dynamic batch. However, If we deploy the model with shape 224-256, the conversion process goes well, but we can't load the converted model.

/Users/cx/opt/miniforge3/envs/mm/lib/python3.9/site-packages/coremltools/models/model.py:145: RuntimeWarning: You will not be able to run predict() on this Core ML model. Underlying exception message was: {
    NSLocalizedDescription = "Error in declaring network.";
}
  _warnings.warn(