Add option to easily test sharding in local

[Neylix]

Is your feature request related to a problem?

Actually we need at least 11 nodes to test sharding (transaction not replicated on all nodes). But this is really complex to run 11 nodes in a local env on 1 computer.

Describe the solution you'd like

We should have something on the config that allow us to easily modify the storage constraints of the election.

Additional context

I think for development a good constraint would be 3 storage nodes. We should think about a way to test the geographical constraint too in local

Epic: #228