Catch exception DatasetGenerationCastError
See https://huggingface.co/datasets/ykcajiad/CS162/discussions/1

The JSONL file is malformed, and `datasets` raises `DatasetGenerationCastError`, but we don't catch it, resulting in an `UnexpectedError`. We should catch it and pass the details to the user so they can fix the data.

```
An error occurred while generating the dataset All the data files must have the same columns, but at some point there are 1 missing columns ({'label'}) This happened while the json dataset builder was generating data using hf://datasets/ykcajiad/CS162/test_claims.jsonl (at revision fe309dd1a7a6627ce93d14d3c32dff5d341291b3) Please either edit the data files to have matching columns, or separate them into different configurations (see docs at https://hf.co/docs/hub/datasets-manual-configuration#multiple-configurations)

Error code:   UnexpectedError
```
Catch exception DatasetGenerationCastError: See https://huggingface.co/datasets/ykcajiad/CS162/discussions/1

The JSONL file is malformed, and `datasets` raises `DatasetGenerationCastError`, but we don't catch it, resulting in an `UnexpectedError`. We should catch it and pass the details to the user so they can fix the data.

```
An error occurred while generating the dataset All the data files must have the same columns, but at some point there are 1 missing columns ({'label'}) This happened while the json dataset builder was generating data using hf://datasets/ykcajiad/CS162/test_claims.jsonl (at revision fe309dd1a7a6627ce93d14d3c32dff5d341291b3) Please either edit the data files to have matching columns, or separate them into different configurations (see docs at https://hf.co/docs/hub/datasets-manual-configuration#multiple-configurations)

Error code:   UnexpectedError
```