[Jepsen] Linearizability failure during disk-failure tests

Linearizability failure seen during kv-engine-jepsen-post-commit-2129. For test lein trampoline run test --nodes-file ./nodes --username vagrant --ssh-private-key ./resources/vagrantkey --install-path /home/couchbase/jenkins/workspace/kv-engine-jepsen-post-commit/install --workload=disk-failure --manipulate-disks --replicas=1 --durability=0:0:0:100 --recovery-type=delta --eviction-policy=full --cas --hashdump --enable-memcached-debug-log-level --enable-tcp-capture --autofailover-timeout=30.

There is a crash dump file but no logging of it in the memcached.logs and its a post-commit build, we'll need to rebuild memached manually to create the right binary to get a backtrace.

Logs attached 20200808T220033.000-0700(1).zip