Revert "gnu: xdg-desktop-portal: Update to 1.18.4."

This reverts commit 1b4304ea29.  This broke
setting themes in GNOME 44.1.

Reported-by: Ada Stevenson <adanskana@gmail.com>
Change-Id: Iaa8632a743d6fefd46f6415010b33f69bd6d2a04

gnu/packages/patches/xdg-desktop-portal-disable-portal-tests.patch

@@ -1,56 +0,0 @@
-From b7750fa99c31c5f28ac2053fa154bef4038b5cc0 Mon Sep 17 00:00:00 2001
-From: dan <i@dan.games>
-Date: Tue, 2 Jul 2024 19:37:38 +0800
-Subject: [PATCH] tests: remove portal tests.
-
----
- tests/meson.build | 24 ------------------------
- 1 file changed, 24 deletions(-)
-
-diff --git a/tests/meson.build b/tests/meson.build
-index a2dafee..bcd87be 100644
---- a/tests/meson.build
-+++ b/tests/meson.build
-@@ -181,18 +181,6 @@ portal_tests = [
- 
- test_env = env_tests
- test_env.set('XDG_CURRENT_DESKTOP', 'test')
--foreach p : portal_tests
--    test(
--      'test-portals-@0@'.format(p),
--      test_portals,
--      args: ['--verbose', '--keep-going', '--tap', '-p', '/portal/@0@'.format(p)],
--      depends: [test_backends, test_portals],
--      env: test_env,
--      is_parallel: false,
--      protocol: test_protocol,
--      suite: 'portals',
--    )
--endforeach
- 
- # Split the portal tests into one test per portal, this makes debugging a lot
- # easier.
-@@ -204,18 +192,6 @@ portal_limited = [
- 
- limited_env = env_tests
- limited_env.set('XDG_CURRENT_DESKTOP', 'limited')
--foreach p : portal_limited
--    test(
--      'limited-portals-@0@'.format(p),
--      limited_portals,
--      args: ['--verbose', '--keep-going', '--tap', '-p', '/limited/@0@'.format(p)],
--      depends: [test_backends, limited_portals],
--      env: limited_env,
--      is_parallel: false,
--      protocol: test_protocol,
--      suite: 'portals',
--    )
--endforeach
- 
- if enable_installed_tests
-   install_data(
-
-base-commit: 11c8a96b147aeae70e3f770313f93b367d53fedd
--- 
-2.41.0
-