add more mixed[] to item namespace

src/pocketmine/item/Banner.php

@@ -97,6 +97,8 @@ class Banner extends Item{
 
 	/**
 	 * Returns the data of a pattern with the given ID.
+	 *
+	 * @return mixed[]
 	 */
 	public function getPatternData(int $patternId) : array{
 		if(!$this->patternExists($patternId)){

src/pocketmine/item/Item.php

@@ -769,6 +769,8 @@ class Item implements ItemIds, \JsonSerializable{
 
 	/**
 	 * Returns an array of item stack properties that can be serialized to json.
+	 *
+	 * @return mixed[]
 	 */
 	final public function jsonSerialize() : array{
 		$data = [
@@ -792,6 +794,7 @@ class Item implements ItemIds, \JsonSerializable{
 
 	/**
 	 * Returns an Item from properties created in an array by {@link Item#jsonSerialize}
+	 * @param mixed[] $data
 	 */
 	final public static function jsonDeserialize(array $data) : Item{
 		$nbt = "";