Use Grafana-native Data Links for implementing drilldown links

[amotl]

We should investigate how we could implement drilldown links using Grafana-native Data Links introduced the other day, see also [1,2,3].

[1] https://grafana.com/blog/2019/08/06/grafana-v6.3-released/#data-links [2] https://community.panodata.org/t/grafana-dashboard-navigation-using-links/144 [3] https://grafana.com/blog/2019/12/10/pro-tips-dashboard-navigation-using-links/#data-links