public Flavor asFlavor(String flavorString) {
        return nodeFlavors.getFlavor(flavorString)
                          .orElseThrow(() -> new IllegalArgumentException("No flavor '" + flavorString + "'"));
    }
Call {@link this#activateTenantHosts()} after this before deploying applications
node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTester.java