Our coverage reports are in sad state https://coveralls.io/github/ckan/ckan, they haven't been running for years and the coverage itself is not really good either. Now that we are considering moving tests all together to Github Actions in #8731, we could easily add uploading coverage reports to those actions as well.

Coveralls itself hasn't had any development in years though, we could consider moving to codecov for example which has active development and has nice integration with github actions and more readable UI in my opinion. We already seem to have some use it with, we could actively start using it https://app.codecov.io/gh/ckan.