bug#18575: package-test-signed should use skip-unless, not expected-result

[Glenn Morris]

Glenn Morris wrote:

> package-test-signed should use skip-unless rather than expected-result.
> The latter can lead to false "failures" when the test succeeds, eg
>
> https://hydra.nixos.org/build/14915239/log/raw

The fact that the test can pass even when epg-check-configuration fails
probably indicates that is the wrong thing to test anyway. The cause on
hydra is probably that HOME does not exist, which causes gpg
--list-config to fail:

  HOME=/tmp/foo/bar  gpg --with-colons --list-config
  gpg: fatal: can't create directory `/tmp/foo/bar/.gnupg': No such file or 
directory

Perhaps tests should bind epg-gpg-home-directory to a suitable value.