You would think that after the confusion this question engendered in the last edition that it would be made clear here. Alas this is not so. Between the leap action and the athletic rules I get at least 2 answers.
If you have a land speed of at least 30ft, you can use the Leap basic action with no check.
Otherwise, you will have to make an Athletics check to Long Jump.
The DC is equal to the distance you're attempting to move. Per the rules for Leap, you have to jump 15ft to entirely clear a 10ft pit, so the DC is 15.
You could also Leap normally, then attempt to use the Grab an Edge reaction to catch and pull yourself up.