testing: Use renamed systemd unit

While the alias is available after enabling the unit, we don't
actually do that in our testing environment (adding a symlink manually
would work too, then again, why not just use the proper name?).

testing/tests/ipv6/rw-compress-ikev2/pretest.dat

@@ -6,8 +6,8 @@ carol::ip6tables-restore < /etc/ip6tables.rules
 moon::ip6tables -I OUTPUT 1 -o eth1 -p icmpv6 --icmpv6-type 2 -j ACCEPT
 alice::"ip route add fec0:\:/16 via fec1:\:1"
 carol::"ip route add fec1:\:/16 via fec0:\:1"
-moon::systemctl start strongswan-swanctl
-carol::systemctl start strongswan-swanctl
+moon::systemctl start strongswan
+carol::systemctl start strongswan
 moon::expect-connection rw
 carol::expect-connection home
 carol::swanctl --initiate --child home