Bump pycryptodome from 3.19.0 to 3.19.1 in /backend/app

Bumps [pycryptodome](https://github.com/Legrandin/pycryptodome) from 3.19.0 to 3.19.1.
- [Release notes](https://github.com/Legrandin/pycryptodome/releases)
- [Changelog](https://github.com/Legrandin/pycryptodome/blob/master/Changelog.rst)
- [Commits](Legrandin/pycryptodome@v3.19.0...v3.19.1)

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

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