flake.lock: Update

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/51d906d2341c9e866e48c2efcaac0f2d70bfd43e?narHash=sha256-WyMj5jGcecD%2BKC8gEs%2BwFth1J1wjisZf8kVZH13f1Zo%3D' (2023-10-21)
  → 'github:NixOS/nixpkgs/3027ba73dfef68eb555fc2fa97aed4e999e74f97?narHash=sha256-u2F0MMYE%2BEfc%2BocruTbtU/wWHuYHWcJafp5zJ%2B%2Bn/YE%3D' (2024-06-15)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/679ea0878edc749f23516ea6d7ffa974c6304bf5?narHash=sha256-9%2BFjCVE1Y7iUKohBF43yD05KoQB%2BFPcw/XL2rlKkjqY%3D' (2023-10-20)
  → 'github:oxalica/rust-overlay/16c8ad83297c278eebe740dea5491c1708960dd1?narHash=sha256-E/T7Ge6ayEQe7FVKMJqDBoHyLhRhjc6u9CmU8MyYfy0%3D' (2024-06-18)
• Removed input 'rust-overlay/flake-utils'
• Removed input 'rust-overlay/flake-utils/systems'
• Updated input 'rust-overlay/nixpkgs':
    'github:NixOS/nixpkgs/96ba1c52e54e74c3197f4d43026b3f3d92e83ff9?narHash=sha256-eKyxW4OohHQx9Urxi7TQlFBTDWII%2BF%2Bx2hklDOQPB50%3D' (2023-04-13)
  → 'github:NixOS/nixpkgs/e6cea36f83499eb4e9cd184c8a8e823296b50ad5?narHash=sha256-WdWDpNaq6u1IPtxtYHHWpl5BmabtpmLnMAx0RdJ/vo8%3D' (2024-06-15)