flake.lock: Update

Flake lock file updates:

• Updated input 'crane':
    'github:ipetkov/crane/afdcd41180e3dfe4dac46b5ee396e3b12ccc967a' (2023-12-24)
  → 'github:ipetkov/crane/0efe36f9232e0961512572883ba9c995aa1f54b1' (2024-01-03)
• Updated input 'fenix':
    'github:nix-community/fenix/8ad4353759945bec3a5f4bfc53efe818bb41e12a' (2023-12-30)
  → 'github:nix-community/fenix/f18b4378cdd7b684713a06aac710f0762f0e0143' (2024-01-06)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/e1e4626ff5f6831c375256bd8d0a153ee104390e' (2023-12-29)
  → 'github:rust-lang/rust-analyzer/e53792b7cbfbee7f26be567bce2ba9dce5d90868' (2024-01-05)
• Updated input 'nickel':
    'github:tweag/nickel/29f4464aa1d94b0c5db94754860b632a54c81414' (2023-12-22)
  → 'github:tweag/nickel/77b9c5791acb6090f262d9381f0fef4411378916' (2024-01-05)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/e1fa12d4f6c6fe19ccb59cac54b5b3f25e160870' (2023-12-25)
  → 'github:NixOS/nixpkgs/63143ac2c9186be6d9da6035fa22620018c85932' (2024-01-02)