Currently, the specs do not provide for a way to pass secrets to pull a container image from a private repository.
This was requested by the Czech and Greek ELIXIR nodes, see here: https://docs.google.com/spreadsheets/d/1vBFhBQ-nFqhSL5dLjQfOWO6x9BzmV9x6l18p9GYRZdQ/edit#gid=0
Contacts: @xhejtman, @viktoriaas, @zagganas & @vergoulis