minor #23217 [Serializer] Fix workaround min php version (ogizanagi)

This PR was merged into the 3.4 branch.

Discussion
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[Serializer] Fix workaround min php version

| Q             | A
| ------------- | ---
| Branch?       | 3.4 <!-- see comment below -->
| Bug fix?      | yes
| New feature?  | no <!-- don't forget updating src/**/CHANGELOG.md files -->
| BC breaks?    | no
| Deprecations? | no <!-- don't forget updating UPGRADE-*.md files -->
| Tests pass?   | yes
| Fixed tickets | #22444 (comment) <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | N/A

Commits
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74db2e6 [Serializer] Fix workaround min php version

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

@@ -81,7 +81,7 @@ public function denormalize($data, $class, $format = null, array $context = arra
         $timezone = $this->getTimezone($context);
 
         if (null !== $dateTimeFormat) {
-            if (null === $timezone && PHP_VERSION_ID < 50600) {
+            if (null === $timezone && PHP_VERSION_ID < 70000) {
                 // https://bugs.php.net/bug.php?id=68669
                 $object = \DateTime::class === $class ? \DateTime::createFromFormat($dateTimeFormat, $data) : \DateTimeImmutable::createFromFormat($dateTimeFormat, $data);
             } else {