Signed-off-by: Antoine Millet <antoine.millet@arkena.com>

Error message was: "RpcError: Not connected to the peer"

With the permission of Romain Degez, CTO of Smartjog.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>

Also removed endpoint close from default on shutdown callback.

This option allow to raise a TimeoutError for each expected response
not arrived on time.