ScreenCast: Update documentation to Pipewire 0.3 API
ScreenCast: Update documentation to Pipewire 0.3 API

matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,flatpak/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,flatpak/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal,matthiasclasen/xdg-desktop-portal