Bump jms/serializer-bundle from 5.4.0 to 5.5.1

Bumps [jms/serializer-bundle](https://github.com/schmittjoh/JMSSerializerBundle) from 5.4.0 to 5.5.1.
- [Release notes](https://github.com/schmittjoh/JMSSerializerBundle/releases)
- [Changelog](https://github.com/schmittjoh/JMSSerializerBundle/blob/master/CHANGELOG.md)
- [Commits](schmittjoh/JMSSerializerBundle@5.4.0...5.5.1)

---
updated-dependencies:
- dependency-name: jms/serializer-bundle
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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