build: bump curve25519-dalek

Bumps the cargo group with 1 update in the /packages/cacti-plugin-ledger-connector-stellar/src/test/rust/demo-contract directory: [curve25519-dalek](https://github.com/dalek-cryptography/curve25519-dalek).


Updates `curve25519-dalek` from 4.1.1 to 4.1.2
- [Release notes](https://github.com/dalek-cryptography/curve25519-dalek/releases)
- [Commits](dalek-cryptography/curve25519-dalek@curve25519-4.1.1...curve25519-4.1.2)

---
updated-dependencies:
- dependency-name: curve25519-dalek
  dependency-type: indirect
  dependency-group: cargo
...

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