flake.lock: Update (#320)

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/297c756ba6249d483c1dafe42378560458842173?narHash=sha256-ezoe/FwfJpA7sskLoLP2iwfwkYnscEFCP6Vk5kPwh9k%3D' (2024-05-10)
  → 'github:nix-community/fenix/a4b7a4acfb44ee78785b0b53667066a9b1e32245?narHash=sha256-FJJMYOmzST4gOiOo4g5XicKKALv8SWqqk2kntpIF3NM%3D' (2024-05-18)
• Updated input 'fenix/nixpkgs':
    'github:nixos/nixpkgs/b211b392b8486ee79df6cdfb1157ad2133427a29?narHash=sha256-CLU5Tsg24Ke4%2B7sH8azHWXKd0CFd4mhLWfhYgUiDBpQ%3D' (2024-05-07)
  → 'github:nixos/nixpkgs/33d1e753c82ffc557b4a585c77de43d4c922ebb5?narHash=sha256-cYApT0NXJfqBkKcci7D9Kr4CBYZKOQKDYA23q8XNuWg%3D' (2024-05-15)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/5bf2f85c8054d80424899fa581db1b192230efb5?narHash=sha256-vLLgYpdtKBaGYTamNLg1rbRo1bPXp4Jgded/gnprPVw%3D' (2024-05-09)
  → 'github:rust-lang/rust-analyzer/83ba42043166948db91fcfcfe30e0b7eac10b3d5?narHash=sha256-EyjtjocGLtB7tqyqwBfadP4y5BBtT5EkoG3kq/zym5U%3D' (2024-05-16)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/8e47858badee5594292921c2668c11004c3b0142?narHash=sha256-q0OFeZqKQaik2U8wwGDsELEkgoZMK7gvfF6tTXkpsqE%3D' (2024-05-11)
  → 'github:NixOS/nixpkgs/e7cc61784ddf51c81487637b3031a6dd2d6673a2?narHash=sha256-H0eCta7ahEgloGIwE/ihkyGstOGu%2BkQwAiHvwVoXaA0%3D' (2024-05-18)
• Updated input 'nixpkgs-master':
    'github:NixOS/nixpkgs/43cf50bd159b0c356e993121a38a5a9e4946a9a0?narHash=sha256-cqDwi2gubg0lSs93FJN25FxY6k5K78JaAj4ULCXd8uw%3D' (2024-05-12)
  → 'github:NixOS/nixpkgs/68ead29211bb9890f494af3a8b5643a831d9d4c4?narHash=sha256-0zL73zK5tB1NbzvB5all6%2B5W9I42RGCENNvddaIjuZg%3D' (2024-05-19)