Upgrade Ruby and Ubuntu to latest in GH action
Upgrade Ruby and Ubuntu to latest in GH action

It was asked for in
https://github.com/openfoodfoundation/openfoodnetwork/pull/6163/ to use
the latest stable Ruby version. It's also better to use Ubuntu's latest
as well.

lin-d-hop/openfoodnetwork,mkllnk/openfoodnetwork,Matt-Yorkley/openfoodnetwork,Matt-Yorkley/openfoodnetwork,openfoodfoundation/openfoodnetwork,mkllnk/openfoodnetwork,openfoodfoundation/openfoodnetwork,openfoodfoundation/openfoodnetwork,lin-d-hop/openfoodnetwork,mkllnk/openfoodnetwork,Matt-Yorkley/openfoodnetwork,lin-d-hop/openfoodnetwork,mkllnk/openfoodnetwork,lin-d-hop/openfoodnetwork,Matt-Yorkley/openfoodnetwork,openfoodfoundation/openfoodnetwork