Bump werkzeug from 2.3.6 to 3.0.1 in /backend

Bumps [werkzeug](https://github.com/pallets/werkzeug) from 2.3.6 to 3.0.1.
- [Release notes](https://github.com/pallets/werkzeug/releases)
- [Changelog](https://github.com/pallets/werkzeug/blob/main/CHANGES.rst)
- [Commits](pallets/werkzeug@2.3.6...3.0.1)

---
updated-dependencies:
- dependency-name: werkzeug
  dependency-type: indirect
...

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