amavis – How to disable SoughtRules in SpamAssassin

I’m running SpamAssassin 3.4 via Amavisd 2.12, installed with yum from EPEL on Amazon Linux 2. According to the SpamAssassin Confluence wiki (here and here), SoughtRules should be disabled, but … I can’t figure out where it’s configured. How do I turn it off?

I’m pretty sure it’s running, because I keep getting cron emails that say

channel: no 'mirrors.sought.rules.yerp.org' record found, channel failed

Googling around, that seems to be tied to SoughtRules, but the only configuration info I can find is on the Plesk forum, which indicates some configuration like

# SoughtRules - SPAMASSASSIN - Apache Software Foundation
CHANNELURL=sought.rules.yerp.org
KEYID=6C6191E3

out to be commented out. But, not only can I not find anything like that, I can’t find anything that seems like it might be related to this at all, anywhere in either /etc/mail/spamassassin or /etc/amavisd.