phoc: add passthru.tests.phosh

In practice, phoc's primary reverse-dependency is phosh, so let's run
the phosh test on phoc updates.

pkgs/applications/misc/phoc/default.nix

@@ -17,6 +17,7 @@
 , libxkbcommon
 , wlroots
 , xorg
+, nixosTests
 }:
 
 let
@@ -70,6 +71,8 @@ in stdenv.mkDerivation rec {
     patchShebangs build-aux/post_install.py
   '';
 
+  passthru.tests.phosh = nixosTests.phosh;
+
   meta = with lib; {
     description = "Wayland compositor for mobile phones like the Librem 5";
     homepage = "https://gitlab.gnome.org/World/Phosh/phoc";