Revert "mailman-wrapper: crazy hack to work around the missing urllib3 dependency"

This reverts commit ce6b2419be, which
was unnecessary (mailman worked just fine on its parent commit).

See #79222.

pkgs/servers/mail/mailman/wrapped.nix

@@ -15,6 +15,6 @@ runCommand "${mailman.name}-wrapped" {
   cd "${mailman}/bin"
   for exe in *; do
     makeWrapper "${mailman}/bin/$exe" "$out/bin/$exe" \
-        --set PYTHONPATH ${makePythonPath ([ mailman python3.pkgs.urllib3 ] ++ archivers)}
+        --set PYTHONPATH ${makePythonPath ([ mailman ] ++ archivers)}
   done
 ''