Installing flatpak from create-usb isn't obvious

[hungrymonkey]

In create-usb documentation, the guide fails to mention that the user needs to download the gpg key and add it to the remote repo. May I add an installation section the documentation?

wget https://flathub.org/repo/flathub.gpg
flatpak remote-add --gpg-import=./flathub.gpg   --collection-id=org.flathub.Stable flathub /media/user/FLATPAKS/.ostree/repo
flatpak install --sideload-repo=/media/user/FLATPAKS/.ostree/repo flathub org.gnome.gedit

https://docs.flatpak.org/en/latest/usb-drives.html

[hungrymonkey]

Related flatpak/flatpak#5484