chore(example/simple): Update flake.lock

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/a1d92660c6b3b7c26fb883500a80ea9d33321be2?narHash=sha256-V5LpfdHyQkUF7RfOaDPrZDP%2Boqz88lTJrMT1%2BstXNwo%3D' (2024-09-20)
  → 'github:nixos/nixpkgs/b5b2fecd0cadd82ef107c9583018f381ae70f222?narHash=sha256-k6YxGj08voz9NvuKExojiGXAVd69M8COtqWSKr6sQS4%3D' (2024-09-28)
• Updated input 'services-flake':
    'github:juspay/services-flake/5960a2c553ba6f5efec8d6aad64219c8fa036e50?narHash=sha256-XTPhu4CKydPlJJJIAH7XtWDRTvEAV5podwWenI9OvGY%3D' (2024-09-18)
  → 'github:juspay/services-flake/a997c1fccf41a10a5ffd9f806185268b15a9a9b9?narHash=sha256-LNzdPD1SFi/UrNqZZJdFOnPKUrhUov8OLo3uNjA6bY8%3D' (2024-09-28)