minor symfony#58277 [VarDumper] Fix DOMCaster test dumps (alexandre-daubois)

This PR was merged into the 7.1 branch.

Discussion
----------

[VarDumper] Fix `DOMCaster` test dumps

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

cc `@xabbuh`

Commits
-------

4201dde [VarDumper] Fix `DOMCaster` test dumps

Author: xabbuh

src/Symfony/Component/VarDumper/Tests/Caster/DOMCasterTest.php

@@ -170,7 +170,10 @@ public function testCastModernText()
         );
     }
 
-    public function testCastAttr()
+    /**
+     * @requires PHP < 8.4
+     */
+    public function testCastAttrPriorToPhp84()
     {
         $attr = new \DOMAttr('attr', 'value');
 
@@ -187,6 +190,26 @@ public function testCastAttr()
         );
     }
 
+    /**
+     * @requires PHP 8.4
+     */
+    public function testCastAttr()
+    {
+        $attr = new \DOMAttr('attr', 'value');
+
+        $this->assertDumpMatchesFormat(<<<'EODUMP'
+            DOMAttr {%A
+              +name: ? string
+              +specified: ? bool
+              +value: ? string
+              +ownerElement: ? ?DOMElement
+              +schemaTypeInfo: ? mixed
+            }
+            EODUMP,
+            $attr
+        );
+    }
+
     /**
      * @requires PHP 8.4
      */
@@ -199,7 +222,7 @@ public function testCastModernAttr()
               +name: ? string
               +value: ? string
               +ownerElement: ? ?Dom\Element
-              +specified: true
+              +specified: ? bool
             }
             EODUMP,
             $attr