Docs: Add whats new link to What's New index page (#39294)
Docs: Add whats new link to What's New index page (#39294)

* Initial draf

* Added the what's new in 8.2 link to the what's new parent page
grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana