Add info about CSV download for Excel in What's new article (#28661)
Add info about CSV download for Excel in What's new article (#28661)

* Add info about CSV download for Excel in What's new article

* Update docs/sources/whatsnew/whats-new-in-v7-3.md

* Update docs/sources/whatsnew/whats-new-in-v7-3.md
grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana