apcupsd: add nixosTests.apcupsd to passthru.tests

pkgs/servers/apcupsd/default.nix

@@ -1,5 +1,6 @@
 { lib, stdenv, fetchurl, pkg-config, systemd, util-linux, coreutils, wall, hostname, man
 , enableCgiScripts ? true, gd
+, nixosTests
 }:
 
 assert enableCgiScripts -> gd != null;
@@ -52,6 +53,8 @@ stdenv.mkDerivation rec {
     done
   '';
 
+  passthru.tests.smoke = nixosTests.apcupsd;
+
   meta = with lib; {
     description = "Daemon for controlling APC UPSes";
     homepage = "http://www.apcupsd.com/";