[rhythmbox/wip/hadess/post-install: 2/3] ci: Add GTK4 tools package

[Bastien Nocera <hadess src gnome org>]

commit 7454f2388408bfeb70b244148a21af75b8a78032
Author: Bastien Nocera <hadess hadess net>
Date:   Wed May 4 09:12:40 2022 +0200

    ci: Add GTK4 tools package
    
    This will be used to run gtk4-update-icon-cache.

 .gitlab-ci.yml | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index c2542e734..69bba1a24 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -11,6 +11,7 @@ variables:
     gtk-doc-tools
     pkg-config
     libgtk-3-dev
+    libgtk-4-bin
     libgstreamer1.0-dev
     libgstreamer-plugins-base1.0-dev
     libgdk-pixbuf2.0-dev