Add priority to jobs - APS V4

### Things to check first

- [X] I have searched the existing issues and didn't find my feature already requested there

### Feature description

**Hello,**

My suggestion is to add priority to the jobs. Something like:
```python
scheduler.add_job(..., priority=1)
```

In my opinion, the priority argument could be an integer, where the higher the value, the higher the processing priority of that job.

### Use case

Some jobs may require a higher priority than others, so I'm sure this would be useful for a number of use cases.