⬆️ Bump fastify from 4.3.0 to 4.8.1

Bumps [fastify](https://github.com/fastify/fastify) from 4.3.0 to 4.8.1.
- [Release notes](https://github.com/fastify/fastify/releases)
- [Commits](fastify/fastify@v4.3.0...v4.8.1)

---
updated-dependencies:
- dependency-name: fastify
  dependency-type: direct:development
...

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