testing: Migrated ikev2 scenarios to swanctl

testing/tests/ikev2/host2host-cert/description.txt

@@ -1,4 +1,6 @@
 A connection between the hosts <b>moon</b> and <b>sun</b> is successfully set up.
-The authentication is based on X.509 certificates. <b>leftfirewall=yes</b> automatically
-inserts iptables-based firewall rules that let pass the tunneled traffic.
+The authentication is based on X.509 certificates.
+<p/>
+Upon the successful establishment of the IPsec tunnel, <b>leftfirewall=yes</b>
+automatically inserts iptables-based firewall rules that let pass the tunneled traffic.
 In order to test the host-to-host tunnel <b>moon</b> pings <b>sun</b>.