Test: fix recent 024.cert_auth regression test failure.

Test: fix recent 024.cert_auth regression test failure.

Starting from Thu, 21 Nov 2024 16:11:06 +0900, buildfarm's
024.cert_auth have started failed on RockyLinux9 regardless the
Pgpool-II versions or PostgreSQL versions. It seems at the timing the
test platform was updated from RockyLinux9.4 to RockyLinux9.5 and
openssl version was updated from 3.0 to 3.2 as well.  The test firstly
revokes the frontend certificate using openssl ca -revoke, and then
generate a separate CRL file using openssl ca -gencrl command. I
suspect that openssl 3.2 now checks the revoked certificate itself and
decides that it is not valid.

Let's see how buildfarm reacts.