update slot resume pointers for step 7543

slots/2/latest.json

@@ -1 +1 @@
-{"worker_id": "slot:2", "checkpoint": "slots/2/checkpoint-4835", "step": 4835, "updated_at": 1776410839}
+{"worker_id": "slot:2", "checkpoint": "slots/2/checkpoint-7543", "step": 7543, "updated_at": 1776416725}