SPIGOT-6888: Add SpawnReason for Vex spawned by Evokers

By: Doc <nachito94@msn.com>

paper-server/nms-patches/net/minecraft/world/entity/monster/EntityEvoker.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/entity/monster/EntityEvoker.java
++++ b/net/minecraft/world/entity/monster/EntityEvoker.java
+@@ -191,7 +191,7 @@
+                 entityvex.setOwner(EntityEvoker.this);
+                 entityvex.setBoundOrigin(blockposition);
+                 entityvex.setLimitedLife(20 * (30 + EntityEvoker.this.random.nextInt(90)));
+-                worldserver.addFreshEntityWithPassengers(entityvex);
++                worldserver.addFreshEntityWithPassengers(entityvex, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPELL); // CraftBukkit - Add SpawnReason
+             }
+ 
+         }