Update OpenSUSE CI (#889)

Author: lenemter

.github/workflows/main.yml

@@ -67,7 +67,7 @@ jobs:
     steps:
       - name: Install dependencies
         run: |
-          zypper addrepo https://download.opensuse.org/repositories/X11:Pantheon/15.6/X11:Pantheon.repo
+          zypper addrepo https://download.opensuse.org/repositories/X11:Pantheon/16.0/X11:Pantheon.repo
           zypper --gpg-auto-import-keys refresh
           zypper --non-interactive install tar git desktop-file-utils gdk-pixbuf-devel libgnome-desktop-3-devel granite6-devel gtk3-devel libhandy-devel lightdm-gobject-devel mutter-devel meson vala gcc
       - uses: actions/checkout@v7