stand: Fix oversight in updating OpenZFS: Add com.klarasystems:vdev_zaps_v2

com.klarasystems:vdev_zaps_v2 is a new feature that the last OpenZFS
import brought in. It needs to be on the list of supported features, but
that update didn't happen so I woke up to a mailbox with multiple
complaints.

CirrusCI test to boot twice with a zpool update inbetween coming later
today.

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