tweaking the threshold for autoscaling
30 jobs is too low for the medium jobs (and for the light ones too). On the other side, I think we can lower the limit for the heavy ones to 20.

<img width="407" alt="Capture d’écran 2024-03-08 à 10 26 57" src="https://github.com/huggingface/datasets-server/assets/1676121/213e1943-3df5-473a-a481-da46396cf3ce">

tweaking the threshold for autoscaling: 30 jobs is too low for the medium jobs (and for the light ones too). On the other side, I think we can lower the limit for the heavy ones to 20.

<img width="407" alt="Capture d’écran 2024-03-08 à 10 26 57" src="https://github.com/huggingface/datasets-server/assets/1676121/213e1943-3df5-473a-a481-da46396cf3ce">
