Test flatpak build
This makes sure the flatpak build actually works and we have the examples available for easy download. This is somewhat based on the GTK+4 flatpak CI test. (cherry picked from commit bcd03848)
This makes sure the flatpak build actually works and we have the examples available for easy download. This is somewhat based on the GTK+4 flatpak CI test. (cherry picked from commit bcd03848)