testing: Add libipsec scenarios that exchange raw ESP packets

testing/tests/libipsec/host2host-cert-raw/posttest.dat

@@ -0,0 +1,7 @@
+moon::swanctl --terminate --ike host-host 2> /dev/null
+moon::systemctl stop strongswan
+sun::systemctl stop strongswan
+moon::iptables-restore < /etc/iptables.flush
+sun::iptables-restore < /etc/iptables.flush
+moon::sysctl --pattern net.ipv4.conf.all.rp_filter --system
+sun::sysctl --pattern net.ipv4.conf.all.rp_filter --system