Under some unknown race condition, it's possible that looking up or

creating a ReviewRequestVisit will fail when viewing a review request.

This isn't the worst thing in the world, and is likely a temporary

problem (probably due to two requests for creating the same

ReviewRequestVisit at once).
Instead of crashing, we now log the failure and continue on.

Tested a successful visit creation and a successful fetch.
Simulated a DoesNotExist and saw it log and continue on.