testing: Negotiate TLS 1.3 for part of the EAP-TLS scenarios

testing/tests/ikev2/rw-eap-ttls-only/hosts/carol/etc/strongswan.conf

@@ -16,5 +16,6 @@ charon-systemd {
 }
 
 libtls {
-  suites = TLS_DHE_RSA_WITH_AES_128_GCM_SHA256, TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
+  version_max = 1.3
+  suites = TLS_AES_128_GCM_SHA256, TLS_AES_256_GCM_SHA384
 }

testing/tests/ikev2/rw-eap-ttls-only/hosts/moon/etc/strongswan.conf

@@ -19,3 +19,7 @@ charon-systemd {
     }
   }
 }
+
+libtls {
+  version_max = 1.3
+}