🐛 `lease4-update` command has no effect and falsely reports success on multithreaded v4.
Reported on support ticket 16333, originally as a HA bug
kea-dhcp4 server configured with multi-threading enabled that handles a
lease4-update will report
IPv4 lease updated. every time without actually adding or updating a lease.
IPv4 lease added. if the lease is not existing i.e. the first time. In any case, it proceeds to effectively add or update the lease.
Git patches for 1.8.0 and 1.8.1