[neon-notifications] Dev Required: xdg-desktop-portal - 1.21.0

[Neon CI]

https://build.neon.kde.org/job/watcher_release_backports-noble_xdg-desktop-portal-noble/454/display/redirect

#<Debian::UScan::DEHS::Package:0x00007b603d6d9b38 @name="xdg-desktop-portal", @debian_uversion="1.18.4", @debian_mangled_uversion="1.18.4", @upstream_version="1.21.0", @upstream_url="https://github.com/flatpak/xdg-desktop-portal/releases/download/1.21.0/xdg-desktop-portal-1.21.0.tar.xz", @status="Newer version available">