Simplify the code of update_dataset()
When we delete and recreate a dataset (or, in the case of a moved dataset: delete the old one and create the new one): we could simplify the code a lot.

The backfill complexity could be used only for the backfill cron job.


Simplify the code of update_dataset(): When we delete and recreate a dataset (or, in the case of a moved dataset: delete the old one and create the new one): we could simplify the code a lot.

The backfill complexity could be used only for the backfill cron job.

