testing: Add expect-connection calls for all tests and hosts

There are some exceptions (e.g. those that use auto=start or p2pnat).

testing/tests/ikev2/net2net-same-nets/pretest.dat

@@ -3,4 +3,5 @@ sun::iptables-restore < /etc/iptables.rules
 moon::ipsec start
 sun::ipsec start
 moon::expect-connection net-net
+sun::expect-connection net-net
 moon::ipsec up net-net