In the CI runs, there is (as of 2023-01-32) around 6000 lines of Unknown reviewer. (see https://github.com/rust-lang/thanks/actions/runs/3982235462/jobs/6826519805)
This means that the contributions are not fully counted and attributed.

There is a FIXME in the code that asks for the reviewer list to be auto-generated.

We should also consider the case where there is shared review ownership. Should we count it as 1/<nb of reviewer> per reviewer, or 1 per reviewer?