docs: offset-based priority is counter-intuitive

[JWPapi]

Path: /runs/priority

Priority traditionally is low first, the way this is built is flexible, but counter-intuitive.

High Priority is getting inserted before low priority.

[nicktrn]

Thanks for flagging @JWPapi! We won't change this for now due to this:

The value for priority is a time offset in seconds that determines the order of dequeuing.

..but we may revisit in the future!