happy ghast is a vehicle

paper-api/src/main/java/org/bukkit/entity/HappyGhast.java

@@ -3,5 +3,5 @@ package org.bukkit.entity;
 /**
  * Represents a happy ghast.
  */
-public interface HappyGhast extends Animals {
+public interface HappyGhast extends Vehicle, Animals {
 }

paper-api/src/main/java/org/bukkit/inventory/EquipmentSlot.java

@@ -13,7 +13,7 @@ public enum EquipmentSlot {
     CHEST(() -> EquipmentSlotGroup.CHEST),
     HEAD(() -> EquipmentSlotGroup.HEAD),
     /**
-     * Only for certain entities such as horses and wolves.
+     * Only for certain entities such as horses, happy ghasts and wolves.
      */
     BODY(() -> EquipmentSlotGroup.BODY),
     /**