Feature Request: Dropdown menu required for external links provided in Grafana dashboard.

### Discussed in https://github.com/grafana/grafana/discussions/63359 <div type='discussions-op-text'> ^{Originally posted by **ErzaScarle** February 15, 2023} When we add links to other dashboards at the top of your current dashboard, it gives us with the option of "drop-down" style. Kindly incorporate similar UI for adding external links to the Grafana dashboards as well. Currently those links appear at the top right, if there are multiple links then it gets clumsy. <img width="910" alt="Screenshot 2023-02-15 at 3 51 02 PM" src="https://user-images.githubusercontent.com/22257397/219001251-ae2711ff-336f-49b1-85aa-d97093950167.png"> </div>