minor symfony#60864 [Serializer] Remove unused variable (mttsch)

This PR was submitted for the 7.3 branch but it was merged into the 7.4 branch instead.

Discussion
----------

[Serializer] Remove unused variable

| Q             | A
| ------------- | ---
| Branch?       | 7.3
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        |
| License       | MIT

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Commits
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62c66b5 [Serializer] Remove unused variable

Author: fabpot

src/Symfony/Component/Serializer/Normalizer/AbstractObjectNormalizer.php

@@ -1053,7 +1053,7 @@ private function updateData(array $data, string $attribute, mixed $attributeValu
      */
     private function isMaxDepthReached(array $attributesMetadata, string $class, string $attribute, array &$context): bool
     {
-        if (!($enableMaxDepth = $context[self::ENABLE_MAX_DEPTH] ?? $this->defaultContext[self::ENABLE_MAX_DEPTH] ?? false)
+        if (!($context[self::ENABLE_MAX_DEPTH] ?? $this->defaultContext[self::ENABLE_MAX_DEPTH] ?? false)
             || !isset($attributesMetadata[$attribute]) || null === $maxDepth = $attributesMetadata[$attribute]?->getMaxDepth()
         ) {
             return false;