* updated the alerting tab.

* changed so we use a confirm button.

* removed uncommeneted import.

* Change to secondary buttons

Co-Authored-By: Dominik Prokop <dominik.prokop@grafana.com>

* trying to fix issue with panel of undefined.

* Fix prettier

* Update public/app/features/alerting/AlertTab.tsx

Co-authored-by: Dominik Prokop <dominik.prokop@grafana.com>