chore(deps): bump the pip group in /backend with 2 updates

Bumps the pip group in /backend with 2 updates: [cryptography](https://github.com/pyca/cryptography) and [tornado](https://github.com/tornadoweb/tornado).


Updates `cryptography` from 42.0.4 to 43.0.1
- [Changelog](https://github.com/pyca/cryptography/blob/main/CHANGELOG.rst)
- [Commits](pyca/cryptography@42.0.4...43.0.1)

Updates `tornado` from 6.4.1 to 6.4.2
- [Changelog](https://github.com/tornadoweb/tornado/blob/v6.4.2/docs/releases.rst)
- [Commits](tornadoweb/tornado@v6.4.1...v6.4.2)

---
updated-dependencies:
- dependency-name: cryptography
  dependency-type: indirect
  dependency-group: pip
- dependency-name: tornado
  dependency-type: indirect
  dependency-group: pip
...

Signed-off-by: dependabot[bot] <[email protected]>