Update symfony/serializer requirement from ^4.0 to ^5.3

[dependabot]

Updates the requirements on symfony/serializer to permit the latest version.

Release notes

Sourced from symfony/serializer's releases.

v5.3.0

Changelog (symfony/serializer@v5.3.0-RC1...v5.3.0)

• no significant changes

Changelog

Sourced from symfony/serializer's changelog.

CHANGELOG

5.3

• Add the ability to provide (de)normalization context using metadata (e.g. @Symfony\Component\Serializer\Annotation\Context)
• Deprecate ArrayDenormalizer::setSerializer(), call setDenormalizer() instead
• Add normalization formats to UidNormalizer
• Add CsvEncoder::END_OF_LINE context option
• Deprecate creating instances of the annotation classes by passing an array of parameters, use named arguments instead

5.2.0

• added CompiledClassMetadataFactory and ClassMetadataFactoryCompiler for faster metadata loading.
• added UidNormalizer
• added FormErrorNormalizer
• added MimeMessageNormalizer
• serializer mapping can be configured using php attributes

5.1.0

• added support for scalar values denormalization
• added support for \stdClass to ObjectNormalizer
• added the ability to ignore properties using metadata (e.g. @Symfony\Component\Serializer\Annotation\Ignore)
• added an option to serialize constraint violations payloads (e.g. severity)

5.0.0

• throw an exception when creating a Serializer with normalizers which neither implement NormalizerInterface nor DenormalizerInterface
• throw an exception when creating a Serializer with encoders which neither implement EncoderInterface nor DecoderInterface
• changed the default value of the CsvEncoder "as_collection" option to true
• removed AbstractNormalizer::$circularReferenceLimit, AbstractNormalizer::$circularReferenceHandler, AbstractNormalizer::$callbacks, AbstractNormalizer::$ignoredAttributes, AbstractNormalizer::$camelizedAttributes, AbstractNormalizer::setCircularReferenceLimit(), AbstractNormalizer::setCircularReferenceHandler(), AbstractNormalizer::setCallbacks() and AbstractNormalizer::setIgnoredAttributes(), use the default context instead.
• removed AbstractObjectNormalizer::$maxDepthHandler and AbstractObjectNormalizer::setMaxDepthHandler(), use the default context instead.
• removed XmlEncoder::setRootNodeName() & XmlEncoder::getRootNodeName(), use the default context instead.
• removed individual encoders/normalizers options as constructor arguments.
• removed support for instantiating a DataUriNormalizer with a default MIME type guesser when the symfony/mime component isn't installed.
• removed the XmlEncoder::TYPE_CASE_ATTRIBUTES constant. Use XmlEncoder::TYPE_CAST_ATTRIBUTES instead.

4.4.0

... (truncated)

Commits

• c8b06ee Merge branch '5.2' into 5.3
• e6b20ac Merge branch '4.4' into 5.2
• 6db3eb4 Fix markdown
• 5e2c296 Merge branch '5.2' into 5.x
• b072c8f Merge branch '4.4' into 5.2
• c9c90ea Fix deprecations from Doctrine Annotations+Cache
• 511953d Fix duplicated legacy test
• fc663b9 Merge branch '5.2' into 5.x
• 3698d26 Merge branch '4.4' into 5.2
• 9db284c [Serializer][Validator] Update some phpDoc relative to "getters"
• Additional commits viewable in compare view

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[dependabot]

Superseded by #26.