The format file has also been renamed to revng-clang-format-style-file.
The check-revng-conventions scripts now always uses the same format
file, unless otherwise specified with the new option
--use-local-clang-format-file.
In this way, the check-revng-conventions uses the same format in all the
projects by default, but if a project needs to customize it (e.g.
cold-revng which follows the Qt style) it can use the new flag to
fallback to using the local .clang-format file.