add break in leaderboard command

commands/leaderboard.js

@@ -17,6 +17,7 @@ module.exports = {
 
         let text = ""
         for(let i = 0; i < 5; i++) {
+            if(data === undefined) break
             text += `${i + 1}. ${data[i].ID} (${data[i].data} cm) `
         }