Fix test failures with openssl security level >= 1

When OpenSSL compiled to run at security level >= 1, certificates signed using SHA-1 aren't allowed. We don't generate or use any such certificates in our regular protocol, but we had a few in our tests.

This commit replaces those certs with the current certs from www.torproject.org.

Closes #41021 (closed). Bugfix on 0.2.8.1 when the tests were introduced.