Wrong parameter's name for Serializer Yaml configuration

[b-viguier]

Serializer's documentation explains that we can specify a context specific to normalization or denormalization using normalizationContext and denormalizationContext keys in Yaml configuration:

https://github.com/symfony/symfony-docs/blob/6.4/serializer.rst?plain=1#L523-L524

# config/serializer/person.yaml
App\Model\Person:
    attributes:
        createdAt:
            contexts:
                - normalizationContext: { datetime_format: 'Y-m-d' }
                  denormalizationContext: { datetime_format: !php/const \DateTime::RFC3339 }

In the other hand, the YamlFileLoader is looking for normalization_context and denormalization_context keys:

https://github.com/symfony/symfony/blob/b43330568c434747ec5efe2aed7c14c7995e551a/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php#L114-L120

if ($context = $line['normalization_context'] ?? false) {
    $attributeMetadata->setNormalizationContextForGroups($context, $groups);
}

if ($context = $line['denormalization_context'] ?? false) {
    $attributeMetadata->setDenormalizationContextForGroups($context, $groups);
}

Links above are for 6.4 but it seems to be there from the beginning, nothing changed in the code. Confusion may be due to the name of the corresponding attribute.