@Override
    public void validate(ChangeContext context) {
        for (var clusterId : context.previousModel().allClusters()) {
            if (context.model().allClusters().contains(clusterId))
                validate(clusterId, context);
        }
    }
Checks that resources per document per node is reduced too much in one go.

@author bratseth
config-model/src/main/java/com/yahoo/vespa/model/application/validation/change/ResourcesReductionValidator.java