⬆️ Upgrade lib : nikic/php-parser

We were on v3 that is no longer maintained and compatibility is annonced for PHP 7.2.
v4 is active and supports PHP up to 8.0
No problem to update as this is only used in the config editor (\Combodo\iTop\Config\Validator\iTopConfigAstValidator)

lib/nikic/php-parser/lib/PhpParser/NodeTraverserInterface.php

@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 
 namespace PhpParser;
 
@@ -9,14 +9,14 @@ interface NodeTraverserInterface
      *
      * @param NodeVisitor $visitor Visitor to add
      */
-    function addVisitor(NodeVisitor $visitor);
+    public function addVisitor(NodeVisitor $visitor);
 
     /**
      * Removes an added visitor.
      *
      * @param NodeVisitor $visitor
      */
-    function removeVisitor(NodeVisitor $visitor);
+    public function removeVisitor(NodeVisitor $visitor);
 
     /**
      * Traverses an array of nodes using the registered visitors.
@@ -25,6 +25,5 @@ interface NodeTraverserInterface
      *
      * @return Node[] Traversed array of nodes
      */
-    function traverse(array $nodes);
+    public function traverse(array $nodes) : array;
 }
-