SPIGOT-7737: Add separate TreeType.MEGA_PINE

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/TreeType.java

@@ -65,6 +65,10 @@ public enum TreeType {
      * Mega redwood tree; 4 blocks wide and tall
      */
     MEGA_REDWOOD,
+    /**
+     * Mega pine tree
+     */
+    MEGA_PINE,
     /**
      * Tall birch tree
      */