We do some merging in a couple of the other tests as well, but the idea
is to have specific test cases that exercise our merge logic.
This one starts simple. Merge a dive with some valid info with a second
one that has less data filled. And then try it in both possible orders.
It shows a few potential problems.
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
