load_dataset_builder should error if "name" does not exist?
Yes I think it should raise an error. Currently it looks like it instantiates a custom configuration with the name given by the user:
https://github.com/huggingface/datasets/blob/ba27ce33bf568374cf23a07669fdd875b5718bc2/src/datasets/builder.py#L391-L397
```
import datasets as ds
builder = ds.load_dataset_builder('sent_comp', name="doesnotexist")
builder.info.config_name
```

returns

```
'doesnotexist'
```

Shouldn't it raise an error instead?

For this dataset, the only valid values for `name` should be: `"default"` or `None` (ie. argument not passed)