Fix docblock for use_language

Signed-off-by: Matt Friedman <[email protected]>

operators/nestedset_rules.php

@@ -45,7 +45,7 @@ public function __construct(\phpbb\db\driver\driver_interface $db, \phpbb\lock\d
 	/**
 	* Set additional sql where restrictions to use the language id
 	*
-	* @param int $language The language selection identifier; default: 0
+	* @param string $language Language selection iso
 	* @return nestedset_rules $this object for chaining calls
 	* @access public
 	*/