flake: update inputs (#425)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/5785b6bb5eaae44e627d541023034e1601455827?narHash=sha256-KOTTUfPkugH52avUvXGxvWy8ibKKj4genodIYUED%2BKc%3D' (2024-10-16)
  → 'github:NixOS/nixpkgs/4c2fcb090b1f3e5b47eaa7bd33913b574a11e0a0?narHash=sha256-/uilDXvCIEs3C9l73JTACm4quuHUsIHcns1c%2BcHUJwA%3D' (2024-10-18)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/9051466c82b9b3a6ba9e06be99621ad25423ec94?narHash=sha256-KDmYxpkFWa0Go0WnOpkgQOypVaQxbwgpEutET5ey1VQ%3D' (2024-10-18)
  → 'github:oxalica/rust-overlay/b259ef799b5ac014604da71ecd92d4a52603ed2d?narHash=sha256-H7KGGJUU9BcDNnfXiATBGgs6FJKWQdfftNJS%2B/v2aMU%3D' (2024-10-19)

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