Add back accidentally dropped Wandering Trader patch (#9492)

patches/server/0988-Only-set-despawnTimer-for-Wandering-Traders-spawned-.patch

@@ -0,0 +1,33 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Jason Penilla <11360596+jpenilla@users.noreply.github.com>
+Date: Fri, 19 Mar 2021 16:07:21 -0700
+Subject: [PATCH] Only set despawnTimer for Wandering Traders spawned by
+ WanderingTraderSpawner
+
+
+diff --git a/src/main/java/net/minecraft/world/entity/npc/WanderingTrader.java b/src/main/java/net/minecraft/world/entity/npc/WanderingTrader.java
+index 2e7de2378e01aed514e237029d6d64e78871c9b4..0002f3a2f2e096d4b2015baf707707f6cc1a9582 100644
+--- a/src/main/java/net/minecraft/world/entity/npc/WanderingTrader.java
++++ b/src/main/java/net/minecraft/world/entity/npc/WanderingTrader.java
+@@ -63,7 +63,7 @@ public class WanderingTrader extends net.minecraft.world.entity.npc.AbstractVill
+ 
+     public WanderingTrader(EntityType<? extends WanderingTrader> type, Level world) {
+         super(type, world);
+-        this.setDespawnDelay(48000); // CraftBukkit - set default from MobSpawnerTrader
++        //this.setDespawnDelay(48000); // CraftBukkit - set default from MobSpawnerTrader // Paper - move back to MobSpawnerTrader - Vanilla behavior is that only traders spawned by it have this value set.
+     }
+ 
+     @Override
+diff --git a/src/main/java/net/minecraft/world/entity/npc/WanderingTraderSpawner.java b/src/main/java/net/minecraft/world/entity/npc/WanderingTraderSpawner.java
+index 5d199fe497bd852827d3d18fb7566a09e70331a3..8385eb1d60f377da94e3178ab506feefb43563fd 100644
+--- a/src/main/java/net/minecraft/world/entity/npc/WanderingTraderSpawner.java
++++ b/src/main/java/net/minecraft/world/entity/npc/WanderingTraderSpawner.java
+@@ -120,7 +120,7 @@ public class WanderingTraderSpawner implements CustomSpawner {
+                     return false;
+                 }
+ 
+-                WanderingTrader entityvillagertrader = (WanderingTrader) EntityType.WANDERING_TRADER.spawn(world, blockposition2, MobSpawnType.EVENT, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NATURAL); // CraftBukkit
++                WanderingTrader entityvillagertrader = (WanderingTrader) EntityType.WANDERING_TRADER.spawn(world, null, trader -> trader.setDespawnDelay(48000), blockposition2, MobSpawnType.EVENT, false, false, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NATURAL); // CraftBukkit // Paper - set despawnTimer before spawn events called
+ 
+                 if (entityvillagertrader != null) {
+                     for (int i = 0; i < 2; ++i) {