Black 23.1.0 is released which, as the first release of the year,
introduces the 2023 stable style. This incorporates most of last year's
preview style.
https://github.com/psf/black/releases/tag/23.1.0
Backport of 097e3a70c1481ee7b042b2edd91b2be86fb7b5b6 from main.
Made the fix in InteractiveMigrationQuestioner class code, rather than
MigrationAutodetector, because --dry-run shouldn't affect whether
MigrationAutodetector will detect non-nullable fields, but the
questioner should skip the question and returns a None for default
(since that won't be used anyway) if --dry-run is used.
