Changes

Unicode changes in Format should be treated as breaking changes (#14272)

See https://github.com/dbuenzli/cmdliner/issues/234 where this potentially causes a testcase that was previously passing on 5.3 to now fail on 5.4.0~beta2.

(cherry picked from commit 11c9a6bb888404ed9a32b879a4440ba790eef095)
 (commit: 4e07432)