nixosTests.writefreely: migrate to runTest

Part of #386873

nixos/tests/all-tests.nix

@@ -1463,7 +1463,7 @@ in
   wpa_supplicant = import ./wpa_supplicant.nix { inherit pkgs runTest; };
   wordpress = runTest ./wordpress.nix;
   wrappers = handleTest ./wrappers.nix { };
-  writefreely = handleTest ./web-apps/writefreely.nix { };
+  writefreely = import ./web-apps/writefreely.nix { inherit pkgs runTest; };
   wstunnel = runTest ./wstunnel.nix;
   xandikos = runTest ./xandikos.nix;
   xautolock = runTest ./xautolock.nix;

nixos/tests/web-apps/writefreely.nix

@@ -1,16 +1,12 @@
 {
-  system ? builtins.currentSystem,
-  config ? { },
-  pkgs ? import ../../.. { inherit system config; },
+  runTest,
+  ...
 }:
 
-with import ../../lib/testing-python.nix { inherit system pkgs; };
-with pkgs.lib;
-
 let
   writefreelyTest =
     { name, type }:
-    makeTest {
+    runTest {
       name = "writefreely-${name}";
 
       nodes.machine =