minor #40728 [PHPDoc] Fix some union type cases (fancyweb)

This PR was merged into the 4.4 branch.

Discussion
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[PHPDoc] Fix some union type cases

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | -
| License       | MIT
| Doc PR        | -

While working on symfony/symfony#40154, I discovered some PHPDoc issues, I'm going to comment in the review. Upper branches will need some fixes too.

Commits
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dd1481642b [PHPDoc] Fix some union type cases

Author: Nyholm

Serializer.php

@@ -66,8 +66,8 @@ class Serializer implements SerializerInterface, ContextAwareNormalizerInterface
     private $normalizerCache = [];
 
     /**
-     * @param (NormalizerInterface|DenormalizerInterface)[] $normalizers
-     * @param (EncoderInterface|DecoderInterface)[]         $encoders
+     * @param array<NormalizerInterface|DenormalizerInterface> $normalizers
+     * @param array<EncoderInterface|DecoderInterface>         $encoders
      */
     public function __construct(array $normalizers = [], array $encoders = [])
     {