void populateAmbariConfiguration(ObjectNode root) {
    root.put(AMBARI_SERVER_CONFIGURATIONS_PROPERTY, mapper.valueToTree(ambariServerConfigurationHandler.getConfigurations()));
  }
Retrieves the Ambari configuration if exists and adds it to services.json

@param root The JSON document that will become service.json when passed to the stack advisor engine
ambari-server/src/main/java/org/apache/ambari/server/api/services/stackadvisor/commands/StackAdvisorCommand.java