- Using `git log` was brittle with name changes and email address changes for
  contributors over the years unless we made a Git `mailmap` file which brings
  with it its own updatedness overhead.
- Let's use the GitHub commits API (importantly _not_ the search API) so that
  we can give it a username and it will return contributions associated with
  every email address on that user's account:
  https://docs.github.com/en/rest/commits/commits?apiVersion=2022-11-28#list-commits--parameters.
- This is quite significantly slower, but it's worth it for correctness
  especially when we get to all maintainers' contributions (in a separate PR).
- The commits API does not (yet?) support trailers or commit "committer"s, just
  authors.

- Functionally it doesn't matter that the URL will have an `&` at the
  end if `additional_query_params` is `nil`, because it doesn't affect
  the URL at all.