Update gigaword card and info
I think it actually comes from an issue here:

https://github.com/huggingface/datasets/blob/810b12f763f5cf02f2e43565b8890d278b7398cd/src/datasets/utils/file_utils.py#L575-L579

and 

https://github.com/huggingface/datasets/blob/810b12f763f5cf02f2e43565b8890d278b7398cd/src/datasets/utils/streaming_download_manager.py#L386-L389

This code doesn't seem to work anymore. This can probably be fixed with

```python
if url.startswith("https://drive.google.com/"): 
    url += "&confirm=t"
    cookies = response.cookies 
```

because Google Drive doesn't return the `download_warning` cookie anymore. Actually it seems that is has been fixed already in https://github.com/huggingface/datasets/pull/3787 :)

I think it should have fixed the gigaword dataset loading @lhoestq The linked PR indeed fixes the issue. This PR is still worth merging IMO to update `gigaword`'s card.
Reported on the forum: https://discuss.huggingface.co/t/error-loading-dataset/14999