Option to check authors list minus last commit, for CI on pull requests?

[takluyver]

We just had a PR on h5py where the authors check in CI asked for an email address which the author had not used in any commit. It turned out this was coming from the generated merge commit that GitHub automatically produces for CI to run tests on. This obviously isn't directly a problem with rever, but it was quite confusing.

Would it be possible to have an option to get the authors list excluding the last commit, which we could use when CI runs on a pull request to ignore the author of the generated merge commit?