testing: Some minor fixes in test scenarios

testing/tests/tnc/tnccs-20-pdp-pt-tls/posttest.dat

@@ -3,6 +3,8 @@ dave::ip route del 10.1.0.0/16 via 192.168.0.1
 winnetou::ip route del 10.1.0.0/16 via 192.168.0.1
 alice::service charon stop
 alice::service apache2 stop
+alice::rm /etc/swanctl/rsa/aaaKey.pem
+alice::rm /etc/swanctl/x509/aaaCert.pem
 alice::iptables-restore < /etc/iptables.flush
 carol::iptables-restore < /etc/iptables.flush
 dave::iptables-restore < /etc/iptables.flush