Bug#959619: urwid: FTBFS: dh_auto_test: error: pybuild --test -i python{version} -p 3.8 returned exit code 13

[Matthias Klose]

I see this on the Launchpad buildds, building the package. Adding a build
dependency on locales-all fixes this.  I assume that the same dependency needs
to be added for the autopkg test.