[neon-notifications] Dev Required: pyside6 - 6.7.3

[Neon CI]

https://build.neon.kde.org/job/watcher_release_qt6_pyside6/55/display/redirect

#<Debian::UScan::DEHS::Package:0x00007f5f23a5be58 @name="pyside6", @debian_uversion="6.7.2", @debian_mangled_uversion="6.7.2", @upstream_version="6.7.3", @upstream_url="https://qt-mirror.dannhauer.de/official_releases/QtForPython/pyside6/PySide6-6.7.3-src/pyside-setup-everywhere-src-6.7.3.tar.xz", @status="Newer version available">