Tests use IO::Async::LoopTests provided by libio-async-perl

IO::Async::LoopTests uses (in Perl sense of use) Test::More
Test::Fatal and Test::Refcount. These modules are not in the run-time
dependency list of libio-async-perl (but are recommended)

So they must be listed as Build-Depends in debian/control.

Ideally, libio-async-perl should be split into a runtime and dev
package.

 -- Dominique Dumont <domi.dumont@free.fr>, Sun,  2 Oct 2016 16:27:20 +0200
