Don't negotiate TLSv1.3 with the ossl_shim

The ossl_shim doesn't know about TLSv1.3 so we should disable that
protocol version for all tests for now.

This fixes the current Travis failures.

[extended tests]

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5593)