test: pin regression test for #8074 to TLS 1.2

This test has a dependency on the order in which the TCP connection is
made, and TLS server handshake completes. It assumes those server side
events occur before the client side write callback, which is not
guaranteed by the TLS API. It usually passes with TLS1.3, but TLS1.3
didn't exist at the time the bug existed.

Pin the test to TLS1.2, since the test shouldn't be changed in a way that
doesn't trigger a segfault in 7.7.3:
- https://github.com/nodejs/node/issues/13184#issuecomment-303700377

PR-URL: https://github.com/nodejs/node/pull/25508


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>