Problem
With the current work going on around testing the graph split, we investigated which of the constraint checks that are using SPARQL queries are affected.
In an investigation (see T355298 for details) we identified that if we do nothing, UniqueValueChecker will produce some false negatives.
So in order for this to run as required, we need to make UniqueValueChecker query a list of endpoints (and configure that list in production).
Acceptance Criteria
- UniqueValueChecker runs as normal and produces no false negatives after the graph split