run: Ensure the font cache dirs are never writable
run: Ensure the font cache dirs are never writable

Otherwise, if the host dirs don't exist we could end
up with a writable non-persistent directory where fontconfig
writes its caches.

handsome-feng/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,handsome-feng/flatpak,flatpak/flatpak,handsome-feng/flatpak,flatpak/flatpak,matthiasclasen/flatpak,handsome-feng/flatpak,matthiasclasen/flatpak,matthiasclasen/flatpak,handsome-feng/flatpak