code: function deployRules({client, rules, secret}) {
    const lastRequest = rulesRequests.get(client.projectId);
  
    return Promise.resolve(lastRequest).then(oldRulesHash => {
      const newRuleHash = hash(rules);
  
      if (oldRulesHash === newRuleHash) {
        return oldRulesHash;
      }
  
      const request = client.rules({rules, secret});
  
      rulesRequests.set(client.projectId, request.then(
        () => newRuleHash,
        () => oldRulesHash
      ));
  
      return request;
    });
  }
docs: Deploy rules for a database project.
  
  It deploy the rules only if the previous deployed rules were different.
  
  @param  {object}     options          Request options
  @param  {RestClient} options.client   Client
  @param  {object}     options.rules    Rules to deploy
  @param  {string}     options.secret   Secret to authenticate the request
  @return {Promise<void,Error>}