More workers
Following #1448 

note that `cache-maintenance` took care of running a backfill for the datasets >5GB:

```
"DatasetTooBigFromDatasetsError,DatasetTooBigFromHubError,DatasetWithTooBigExternalFilesError,DatasetWithTooManyExternalFilesError"
```
More workers: Following #1448 

note that `cache-maintenance` took care of running a backfill for the datasets >5GB:

```
"DatasetTooBigFromDatasetsError,DatasetTooBigFromHubError,DatasetWithTooBigExternalFilesError,DatasetWithTooManyExternalFilesError"
```