Allow enabling sand duping (#10191)

Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.

patches/server/0863-Add-Mob-Experience-reward-API.patch

@@ -0,0 +1,22 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: GodOfPro <1387ilia@gmail.com>
+Date: Tue, 11 Apr 2023 16:31:39 +0430
+Subject: [PATCH] Add Mob Experience reward API
+
+
+diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
+index ad293ad9d5dcd7836a4fa29b4b687346e3ae516c..31f62fbb54ec7b270fbd8afba7bd7c4bfafa09e3 100644
+--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
++++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
+@@ -170,4 +170,11 @@ public abstract class CraftMob extends CraftLivingEntity implements Mob {
+         this.getHandle().setAggressive(aggressive);
+     }
+     // Paper end
++
++    // Paper start
++    @Override
++    public int getPossibleExperienceReward() {
++        return getHandle().getExperienceReward();
++    }
++    // Paper end
+ }