Add login comment in code snippets
Example:

```python
from datasets import load_dataset

# Login using e.g. `huggingface-cli login` to access this dataset
ds = load_dataset("imagenet-1k")
```

The comment is only show for datasets that require a token to be accessed

Close https://github.com/huggingface/datasets-server/issues/2619
Add login comment in code snippets: Example:

```python
from datasets import load_dataset

# Login using e.g. `huggingface-cli login` to access this dataset
ds = load_dataset("imagenet-1k")
```

The comment is only show for datasets that require a token to be accessed

Close https://github.com/huggingface/datasets-server/issues/2619