The current execution is running slowly for now. It's a simple loop over the mapping
file (one line is one origin) to trigger the ingestion per origin.
Make it go faster using the actual loader_oneshot.
For this, we need to iterate over the mapping file and send tasks
swh.loader.mercurial.tasks.LoadMercurial with the proper parameters.
That also have the following pros:
- no need to deploy another special worker
- have the systemctl logs pushed to elk, which make it browsable more easily (at least for staff)