Zendesk API Enhances Rate Limit Monitoring

## Purpose
Securely use the Zendesk API

## As-Is
Currently, you have to go to [Zendesk - Admin Center - Apps & Integrations - Zendesk API - Activity] page to see the rate limit for the Zendesk API.

* When the rate limit is reached, there is no quick response, which may lead to a failure of the API user.

## To-Be
Zendesk API also integrates with Slack for performance monitoring