script allow application name than are invalid for flatpak
If flatpak don't allow - in name, script should probably forbid it.
After created without problem an app template, the build from gnome-builder failed with this : flatpak build-init --type=app --arch=x86_64 /home/user/.cache/gnome-builder/projects/gtk-rs-todo_template/flatpak/staging/x86_64-main org.gtk-rs.Todo.Devel org.gnome.Sdk org.gnome.Platform 40 --sdk-extension=org.freedesktop.Sdk.Extension.rust-stable error: 'org.gtk-rs.Todo.Devel' is not a valid application name: Only last name segment can contain -