feat: support for schedule: @hourly/@daily/@monthly

## Is your feature request related to a problem?

Using @hourly/@daily/... is easier to remember than using combinations of numbers and stars :)

## Describe the solution you'd like

Just allow using robfig/cron to use the descriptor support.

## Describe alternatives you've considered

Not to? Still fine.

## Use case

Just make things more user-friendly.

## Additional context

N/A.