Made KillCommand set the player health to 0 to allow it to work in Creative. Fixes BUKKIT-2949

By: EvilSeph <evilseph@gmail.com>

paper-api/src/main/java/org/bukkit/command/defaults/KillCommand.java

@@ -30,7 +30,7 @@ public class KillCommand extends VanillaCommand {
             if (ede.isCancelled()) return true;
 
             ede.getEntity().setLastDamageCause(ede);
-            player.damage(ede.getDamage());
+            player.setHealth(0);
             sender.sendMessage("Ouch. That look like it hurt.");
         } else {
             sender.sendMessage("You can only perform this command as a player");