chore(nix): bump rust-overlay from 77265d2 to 83a17eb (#50)

Bumps [rust-overlay](https://github.com/oxalica/rust-overlay) from `77265d2` to `83a17eb`.
- [Commits](oxalica/rust-overlay@77265d2...83a17eb)

---
updated-dependencies:
- dependency-name: rust-overlay
  dependency-version: 83a17ebffcfacb17b49e1b5e9dc15eed07936648
  dependency-type: direct:production
...

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