This test has two issues causing it to not fully delete the documents it is attempting to delete. The first is that it isn't checking the command response of the deletes meaning that a delete which doesn't throw but also doesn't delete anything due to a write error will just silently move on. The second is that it doesn't use the same pattern as many of our other sharding tests which is to enable retryable writes for writes to the config database. This allows writes to be retried in the face of a config server stepdown.