Issue: ExpectedMoreSplits error when loading C4 dataset

### Describe the bug

I encounter bug when running the example command line 

```python
    python main.py \
    --model decapoda-research/llama-7b-hf \
    --prune_method wanda \
    --sparsity_ratio 0.5 \
    --sparsity_type unstructured \
    --save out/llama_7b/unstructured/wanda/ 
```

The bug occurred at these lines of code (when loading c4 dataset) 

```python
traindata = load_dataset('allenai/c4', 'allenai--c4', data_files={'train': 'en/c4-train.00000-of-01024.json.gz'}, split='train')
valdata = load_dataset('allenai/c4', 'allenai--c4', data_files={'validation': 'en/c4-validation.00000-of-00008.json.gz'}, split='validation')
```

The error message states:
```    
raise ExpectedMoreSplits(str(set(expected_splits) - set(recorded_splits)))                                                                           
datasets.utils.info_utils.ExpectedMoreSplits: {'validation'}
```



### Steps to reproduce the bug

1. I encounter bug when running the example command line 


### Expected behavior

The error message states:
```    
raise ExpectedMoreSplits(str(set(expected_splits) - set(recorded_splits)))                                                                           
datasets.utils.info_utils.ExpectedMoreSplits: {'validation'}
```



### Environment info

I'm using cuda 12.4, so I use ```pip install pytorch``` instead of conda provided in install.md

Also, I've tried another environment using the same commands in install.md, but the same bug occured 

Comments:
Hi ! We updated the `allenai/c4` repository to allow people to specify which language to load easily (the the [c4 dataset page](https://huggingface.co/datasets/allenai/c4))

To fix this issue **you can update** `datasets` and remove the mention of the legacy configuration name "allenai--c4":

```python
traindata = load_dataset('allenai/c4', data_files={'train': 'en/c4-train.00000-of-01024.json.gz'}, split='train')
valdata = load_dataset('allenai/c4', data_files={'validation': 'en/c4-validation.00000-of-00008.json.gz'}, split='validation')
```

Did you solve this problem？I have the same bug.It is no use to delete "allenai--c4".

Did you solve it? I met this problem too.

But after I romove allenai--c4,it still fails

For me it works this way. I'm using datasets version 2.17.0

First,  pip install --upgrade datasets.
Second, Update the following two lines of code in data.py (in lib)
traindata = load_dataset('allenai/c4', data_files={'train': 'en/c4-train.00000-of-01024.json.gz'}, split='train')
valdata = load_dataset('allenai/c4', data_files={'validation': 'en/c4-validation.00000-of-00008.json.gz'}, split='validation')

The error is in the Wanda repository: https://github.com/locuslab/wanda
- https://github.com/locuslab/wanda/issues/57

Concretely, in these code lines:
https://github.com/locuslab/wanda/blob/8e8fc87b4a2f9955baa7e76e64d5fce7fa8724a6/lib/data.py#L43-L44

Please report there and/or make the fix in their code.

> traindata = load_dataset('allenai/c4', data_files={'train': 'en/c4-train.00000-of-01024.json.gz'}, split='train')
> valdata = load_dataset('allenai/c4', data_files={'validation': 'en/c4-validation.00000-of-00008.json.gz'}, split='validation')

Solved for me ! Thanks!