Add missing comment
Part of https://github.com/huggingface/dataset-viewer/issues/1443
Currently we have 414 entries with UnexpectedErrorCode because of missing comment value:
`{kind:"dataset-compatible-libraries", http_status:{$ne:200}, "details.cause_exception":"KeyError", "details.copied_from_artifact":{$exists:false}}`

```
  File "/src/services/worker/src/worker/job_runners/dataset/compatible_libraries.py", line 507, in get_compatible_libraries_for_csv
    loading_code["code"] = DASK_CODE.format(function=function, dataset=dataset, pattern=pattern)
KeyError: 'comment'
```

Add missing comment: Part of https://github.com/huggingface/dataset-viewer/issues/1443
Currently we have 414 entries with UnexpectedErrorCode because of missing comment value:
`{kind:"dataset-compatible-libraries", http_status:{$ne:200}, "details.cause_exception":"KeyError", "details.copied_from_artifact":{$exists:false}}`

```
  File "/src/services/worker/src/worker/job_runners/dataset/compatible_libraries.py", line 507, in get_compatible_libraries_for_csv
    loading_code["code"] = DASK_CODE.format(function=function, dataset=dataset, pattern=pattern)
KeyError: 'comment'
```
