This allows to refactor the redundancy between nodes.
I kept out of the refactor loop the gateway for now because it's diverging a bit much
with other nodes (I'm not fluent enough yet with terraform dsl to understand how i can make it comply)
In the next commit (D1807), we'll see how to use that refactoring to declare a new node
without too many duplication.
@douardda might be interested by it since we talked about it ;)