QueryAnalysisCoordinator::getNewConfigurationsForSampler will update the last ping time of one of its samplers to now and then later assert that at least one sampler has a last ping time within a threshold. However, the notion of "now" used when updating the sampler's last ping time and calculating the last ping threshold are not the same, so if the system is very slow, it's possible that the just updated sampler is no longer within the threshold, leading to the invariant being violated.

Instead, _getMinLastPingTime() should accept now as a parameter, so we can ensure that the whole function is using a single notion of "now."