CT_POLICY_EVAL_CTX_set_time expects milliseconds, but given seconds

This resulted in the SCT timestamp check always failing, because the
timestamp appeared to be in the future.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3260)