fix objective indexing

org-cyf/content/js3/success/index.md

@@ -9,7 +9,7 @@ backlog= "Module-JS3"
 [[objectives]]
 1="Every trainee has received and responded to at least one code review"
 2="Every trainee has deployed their pair-coded JS3 Module Project, having completed levels 100 to 500"
-4="70% of cohort is at or beyond milestones"
+3="70% of cohort is at or beyond milestones"
 +++
 
 Every module, you must review your progress to understand if your cohort can progress to the next stage. The conditions for success are listed below. If your cohort has met all of these conditions, you can progress to the next module. If you have not met them yet, what actions will you take to meet them?