⬆ Bump bcrypt from 4.0.1 to 4.3.0 in /backend (#1601)

Bumps [bcrypt](https://github.com/pyca/bcrypt) from 4.0.1 to 4.3.0.
- [Changelog](https://github.com/pyca/bcrypt/blob/main/release.py)
- [Commits](https://github.com/pyca/bcrypt/compare/4.0.1...4.3.0)

---
updated-dependencies:
- dependency-name: bcrypt
  dependency-version: 4.3.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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