jobs/swh-packages: Add swh-coarnotify

There is a new project in town the stack: https://gitlab.softwareheritage.org/swh/devel/swh-coarnotify.

Context: https://gitlab.softwareheritage.org/product-management/coarnotify-service/-/blob/main/README.md

Issue: https://gitlab.softwareheritage.org/product-management/coarnotify-service/-/issues/4