SPIGOT-5464: Add BEEHIVE SpawnReason for when a bee leaves a beehive

src/main/java/org/bukkit/event/entity/CreatureSpawnEvent.java

@@ -169,6 +169,10 @@ public class CreatureSpawnEvent extends EntitySpawnEvent {
          * When an entity is spawned as part of a patrol
          */
         PATROL,
+        /**
+         * When a bee is released from a beehive/bee nest
+         */
+        BEEHIVE,
         /**
          * When a creature is spawned by plugins
          */