Cleaned up random-block-ticking registration

src/pocketmine/block/Block.php

@@ -263,6 +263,15 @@ class Block extends Position implements BlockIds, Metadatable{
 		return false;
 	}
 
+	/**
+	 * Returns whether random block updates will be done on this block.
+	 *
+	 * @return bool
+	 */
+	public function ticksRandomly() : bool{
+		return false;
+	}
+
 	/**
 	 * AKA: Block->isPlaceable
 	 * @return bool