minor #38227 [VarDumper] deal with errors being thrown on PHP 8 (xabbuh)

This PR was merged into the 3.4 branch.

Discussion
----------

[VarDumper] deal with errors being thrown on PHP 8

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       |
| License       | MIT
| Doc PR        |

Commits
-------

6175d528e8 deal with errors being thrown on PHP 8

src/Symfony/Component/VarDumper/Caster/SplCaster.php

@@ -108,6 +108,14 @@ class SplCaster
 
                 $a[$prefix.'⚠'] = 'The parent constructor was not called: the object is in an invalid state';
 
+                return $a;
+            } catch (\Error $e) {
+                if ('Object not initialized' !== $e->getMessage()) {
+                    throw $e;
+                }
+
+                $a[$prefix.'⚠'] = 'The parent constructor was not called: the object is in an invalid state';
+
                 return $a;
             }
         }