roundcube: 1.3.10 -> 1.4.0

https://roundcube.net/news/2019/11/09/roundcube-1.4.0-released

* `curl` cmd in the test can fail as roundcube returns a http/401 if
  unauthorized (and we're explicitly requesting the login form). By
  checking if the `persistent_login` plugin is loaded, the assertion is
  still valid)

* Use `$argv[0]` to determine install path in the installer script. I'm
  not exactly sure why, but it seems as `__DIR__` now resolves symlinks
  which breaks the installer if roundcube is in a `buildEnv` with
  third-party plugins.

nixos/tests/roundcube.nix

@@ -25,6 +25,6 @@ import ./make-test-python.nix ({ pkgs, ...} : {
     roundcube.wait_for_unit("postgresql.service")
     roundcube.wait_for_unit("phpfpm-roundcube.service")
     roundcube.wait_for_unit("nginx.service")
-    roundcube.succeed("curl -sSfL http://roundcube/ | grep 'Keep me logged in'")
+    roundcube.succeed("curl -sSL http://roundcube/ | grep 'Keep me logged in'")
   '';
 })