Currently implements both a format hook to remove white-space paragraphs, and a check to make their existence a critical failure.
In the end may implement only one or none of these, subject to major design changes.
Solves #5409
Co-authored-by: Darragh Elliott <me@delliott.net>
Reviewed-on: #5431
Co-authored-by: delliott <delliott@fsfe.org>
Co-committed-by: delliott <delliott@fsfe.org>
