Update scoreboard.js (#3318)

Author: vicdum

lib/plugins/scoreboard.js

@@ -18,6 +18,7 @@ function inject (bot) {
       delete scoreboards[packet.name]
 
       for (const position in ScoreBoard.positions) {
+        if (!ScoreBoard.positions[position]) continue
         const scoreboard = ScoreBoard.positions[position]
 
         if (scoreboard && scoreboard.name === packet.name) {