private void addOtelcol(TreeConfigProducer<?> parent, DeployState deployState, HostResource hostResource) {
        var otelcol = new OpenTelemetryCollector(parent);
        otelcol.setHostResource(hostResource);
        otelcol.initService(deployState);
    }
Builds the admin model from a V2 admin XML tag.

@author vegardh
config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomAdminV2Builder.java