flake.lock: Update

Flake lock file updates:

• Updated input 'darwin':
    'github:lnl7/nix-darwin/d6703b988728b89456b32bac242c8689902e5a5b?narHash=sha256-7PwlnEQDIbww8%2Bnk0CHLeYTYMA23F/CkynHsX7Mxk%2Bs%3D' (2024-08-21)
  → 'github:lnl7/nix-darwin/a8968d88e5a537b0491f68ce910749cd870bdbef?narHash=sha256-P5zMA17kD9tqiqMuNXwupkM7buM3gMNtoZ1VuJTRDE4%3D' (2024-08-22)
• Updated input 'nixos-unstable':
    'github:nixos/nixpkgs/8a3354191c0d7144db9756a74755672387b702ba?narHash=sha256-Grh5PF0%2BgootJfOJFenTTxDTYPidA3V28dqJ/WV7iis%3D' (2024-08-18)
  → 'github:nixos/nixpkgs/c374d94f1536013ca8e92341b540eba4c22f9c62?narHash=sha256-Z/ELQhrSd7bMzTO8r7NZgi9g5emh%2BaRKoCdaAv5fiO0%3D' (2024-08-21)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/d13fa5a45a34e7c8be33474f58003914430bdc5a?narHash=sha256-G7Mf9uN9m8FimeP3eMHu/dOC4QS8QAzo0h4ZIlDHcCA%3D' (2024-08-20)
  → 'github:nixos/nixpkgs/36a9aeaaa17a2d4348498275f9fe530cd4f9e519?narHash=sha256-z4nw9HxkaXEn%2B5OT8ljLVL2oataHvAzUQ1LEi8Fp%2BSY%3D' (2024-08-21)