Does not respect "auto" setting

## Prerequisites
- [x] I have searched open and closed issues for duplicates.

## Describe the bug
When the *Manual* hour range is set, it applies it even when *Dusk till dawn* is selected (not sure what it is called in english).

### To Reproduce
Steps to reproduce the behavior:
1. Go to System settings/Monitors/Night light (**before sundown**)
2. Set the *Manual* hour range to something that includes the current time
3. Select *Dusk till dawn* (it should turn off the night light)
4. The night light remains active

### Expected behavior
The night light should respect the selected setting.

## Platform Information

- [ ] I'm using the latest version from git that I've manually compiled
- [x] I'm using the latest released stable version

## Additional context