* wip: start on refactoring settings
* settings: progress on settings refactor
* refactor: progress on settings refactoring
* fix: fixed failing test
* settings: moved smtp settings from global to instance
Alerting for prometheus have been depending on the step parameter from each query.
In https://github.com/grafana/grafana/pull/9226 we changed the behavior for step in the
frontend which caused problems for alerting. This commit fixes that by introducing a default
min interval value so alerting always have something to depend on.
closes#9777
