nixos/dante: order after network-online.target (#34435)

network-online.target properly depends on the underlying network
management tool (e.g. NixOS static configuration scripts, dhcpcd,
NetworkManager, networkd) signalling that all interfaces are up and
appropriately configured (to whatever degree possible/required), whereas
network.target only indicates that the network management tool itself
has started.

nixos/modules/services/networking/dante.nix

···
 
     systemd.services.dante = {
       description   = "Dante SOCKS v4 and v5 compatible proxy server";
-      after         = [ "network.target" ];
+      after         = [ "network-online.target" ];
       wantedBy      = [ "multi-user.target" ];
 
       serviceConfig = {