`await LocaleSettings.setLocale` inside a `testWidgets` body waits on a
deferred library load that only completes on the real event loop, so the
regex-dialog test hung indefinitely rather than failing. It passed only
because an earlier plain `test` in the same file loads `de` first —
running the file alone, under a name filter, or sharded apart from that
test stalled the run until the ten-minute timeout.
edde746