Parquet files should be deleted if a dataset goes above the limit
In step /parquet-and-dataset-info, we fail fast if the dataset is too big. But we miss a corner case: if the dataset was under the limit, but is later updated and ends with a size above the limit. In that case, it already contains parquet files in the `refs/convert/parquet` branch. When the dataset is updated (webhook received, jobs launched), an error is stored in the cache. Still, the parquet files on the Hub remain unchanged, corresponding to the last working version, which means they might now be unsynchronized with the `main` branch.

Parquet files should be deleted if a dataset goes above the limit: In step /parquet-and-dataset-info, we fail fast if the dataset is too big. But we miss a corner case: if the dataset was under the limit, but is later updated and ends with a size above the limit. In that case, it already contains parquet files in the `refs/convert/parquet` branch. When the dataset is updated (webhook received, jobs launched), an error is stored in the cache. Still, the parquet files on the Hub remain unchanged, corresponding to the last working version, which means they might now be unsynchronized with the `main` branch.
