Churn nodes causes transaction validation failure

[ghost]

What happened?

When a validation node is stopped and rejoin just after (as a churning node), this cause the transaction validation to fail, and raises a "Invalid validation node election" error.
So the rejoining nodes will not validate the transaction as the election is invalid

What is expected ?

When a validation node is stopped and restarted right away, when the node comes back alive to the network, the validation node should be able to process transactions as if it never leave the network.

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Epic: #306

[ghost]

Reason seems to be the list of authorized nodes is not the same from the two nodes P2P view when the second node is restarting