minor symfony#57558 [VarDumper] take the new DOM HTMLElement class into account (xabbuh)

This PR was merged into the 7.1 branch.

Discussion
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[VarDumper]  take the new DOM HTMLElement class into account

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

Commits
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56bc624 take the new DOM HTMLElement class into account

Author: nicolas-grekas

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

@@ -227,7 +227,7 @@ public function testCastModernElement()
         $attr = \Dom\HTMLDocument::createEmpty()->createElement('foo');
 
         $this->assertDumpMatchesFormat(<<<'EODUMP'
-            Dom\Element {%A
+            Dom\HTMLElement {%A
               +tagName: ? string
             %A}
             EODUMP,