While triaging WT-12894, Mick observed that the "real" bug was test/format getting OOM-killed. We may not pick up OOM via the exit code, so we should add some way to detect this.

Some ideas include (but are not limited to!):

• A grep in /var/log/messages or /var/log/kern.log for kill to confirm the OOM in these cases
• Asking systemd what got OOM-killed

This should be plumbed in such a way that it's easy to add a BBUI rule to detect these. It should also not be limited to test/format, ideally being extended to all WT testing.