[ticket/17176] Cleaned up psalm stubs folder

PHPBB3-17176

build/psalm/stubs/apcu.php

@@ -0,0 +1,35 @@
+<?php
+/**
+ *
+ * This file is part of the phpBB Forum Software package.
+ *
+ * @copyright (c) phpBB Limited <https://www.phpbb.com>
+ * @license GNU General Public License, version 2 (GPL-2.0)
+ *
+ * For full copyright and license information, please see
+ * the docs/CREDITS.txt file.
+ *
+ */
+
+class APCUIterator implements Iterator
+{
+	public function current()
+	{
+	}
+
+	public function next()
+	{
+	}
+
+	public function key()
+	{
+	}
+
+	public function valid()
+	{
+	}
+
+	public function rewind()
+	{
+	}
+}