API: v3.9.1

🔧 Chores

• - api: Use custom user agent to make precheck request (PR #118 by @vvatelot)
• - api: Bump API version to 3.9.1 (commit by @vvatelot)

Docker images

Docker images have been built and pushed to Docker Hub. You can find them here:

• Backend: vvatelot/ecoindex-api-backend:3.9.1
• Worker: vvatelot/ecoindex-api-worker:3.9.1