Not only Ubuntu Focal builds openssl with OPENSSL_TLS_SECURITY_LEVEL=2,
but for some unfathomable reason it patches openssl sources to disable
TLS < 1.2 at security level 2, even though openssl manual says it
should only happen at level 4:
https://www.openssl.org/docs/man1.1.0/man3/SSL_CTX_set_security_level.html

We test TLSv1.1 and TLSv1, so we have to override Focal defaults in mtr.