reduce writes for logged in users

Author: laurelfan

dashboard/app/models/user.rb

@@ -560,7 +560,7 @@ def track_script_progress(script)
 
       update = {}
       update[:started_at] = time_now unless user_script.started_at
-      update[:last_progress_at] = time_now 
+      update[:last_progress_at] = time_now unless user_script.last_progress_at
 
       if !user_script.completed_at && user_script.check_completed?
         update[:completed_at] = time_now