Update ponos api url

The URL of the Ponos-related endpoints have changed from /ponos/ to /api/ since its ingestion in Arkindex's backend. It made some tests fail as in the job below.

https://gitlab.com/teklia/workers/base-worker/-/jobs/3723675204

changed milestone to %ML Prod - February 2023 n°1

added P1 label

requested review from @babadie

assigned to @schneider-y

merged