[PHPUnit100] Skip already key = null on RemoveNamedArgsInDataProviderRector (#475)

* [PHPUnit100] Skip already key = null on RemoveNamedArgsInDataProviderRector

* [ci-review] Rector Rectify

---------

Co-authored-by: GitHub Action <actions@github.com>

Author: samsonasik

rules/PHPUnit100/Rector/Class_/RemoveNamedArgsInDataProviderRector.php

@@ -128,6 +128,10 @@ private function handleArray(Array_ $array): bool
                 continue;
             }
 
+            if (! $item->key instanceof Expr) {
+                continue;
+            }
+
             if (! $item->key instanceof Int_ && $item->key instanceof Expr) {
                 $item->key = null;
                 $hasChanged = true;