test: replace s_client in test-https-ci-reneg-attack

Replace `s_client` in test-https-ci-reneg-attack with built-in
client calling `tls.renegotiate()`. This also fixes the currently-broken
test. (It is broken due to a change in behavior in a
recently-updated-in-core version of `s_client`.)

PR-URL: https://github.com/nodejs/node/pull/25720


Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>