nixos/dokuwiki: add passthru test

pkgs/servers/web-apps/dokuwiki/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchFromGitHub, writeText }:
+{ lib, stdenv, fetchFromGitHub, writeText, nixosTests }:
 
 stdenv.mkDerivation rec {
   pname = "dokuwiki";
@@ -45,6 +45,10 @@ stdenv.mkDerivation rec {
     cp ${phpPluginsLocalConfig} $out/share/dokuwiki/conf/plugins.local.php
   '';
 
+  passthru.tests = {
+    inherit (nixosTests) dokuwiki;
+  };
+
   meta = with lib; {
     description = "Simple to use and highly versatile Open Source wiki software that doesn't require a database";
     license = licenses.gpl2;