Poudriere build of rust fails on 13.1

From: David Mehler <dave.mehler_at_gmail.com>
Date: Mon, 06 Jun 2022 15:00:22 UTC
Hello,

I've got a poudriere system running 13.1-RELEASE and the latest ports
tree. I'm atempting to install both the security/clamav and
security/clamav-unofficial-sigs ports, both of which are failing
because a port needed for building namely lang/rust is failing to
build. I read the failure log but can make no sense of it. Has anyone
else seen this and is there a fix? Suggestions very welcome.

Thanks.
Dave.