flake.lock: Update

Flake lock file updates:

• Updated input 'devshell':
    'github:numtide/devshell/cc8700135fb0740199ac248063f20c6b1a3c7e42' (2024-07-26)
  → 'github:numtide/devshell/67cce7359e4cd3c45296fb4aaf6a19e2a9c757ae' (2024-07-27)
• Removed input 'devshell/flake-utils'
• Removed input 'devshell/flake-utils/systems'
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/a1cc729dcbc31d9b0d11d86dc7436163548a9665' (2024-07-25)
  → 'github:NixOS/nixpkgs/12bf09802d77264e441f48e25459c10c93eada2e' (2024-07-29)
• Updated input 'treefmt-nix':
    'github:numtide/treefmt-nix/8db8970be1fb8be9c845af7ebec53b699fe7e009' (2024-07-23)
  → 'github:numtide/treefmt-nix/768acdb06968e53aa1ee8de207fd955335c754b7' (2024-07-30)