private void storeCompletion(ApplicationId appId, ClusterSpec.Id clusterId, NodeRepository nodeRepository) {
        try (var lock = nodeRepository.applications().lock(appId)) {
            var app = nodeRepository.applications().require(appId);
            var cluster = app.cluster(clusterId).get();
            cluster = cluster.with(cluster.lastScalingEvent().get().withCompletion(nodeRepository.clock().instant()));
            app = app.with(cluster);
            nodeRepository.applications().put(app, lock);
        }
    }
Tests the scaling suggestions maintainer integration.
The specific suggestions are not tested here.

@author bratseth
node-repository/src/test/java/com/yahoo/vespa/hosted/provision/maintenance/ScalingSuggestionsMaintainerTest.java