Adds a column to help the operator see if they configured HRA.Spec.ScheduledOverrides correctly, in a form of "next override schedule recognized by the controller":
```
$ k get horizontalrunnerautoscaler
NAME MIN MAX DESIRED SCHEDULE
actions-runner-aos-autoscaler 0 5 0
org 0 5 0 min=0 time=2021-05-21 15:00:00 +0000 UTC
```
Ref https://github.com/actions-runner-controller/actions-runner-controller/issues/484