chore(test): Update flake.lock

Flake lock file updates:

• Updated input 'flake-parts':
    'github:hercules-ci/flake-parts/f7c1a2d' (2026-05-13)
  → 'github:hercules-ci/flake-parts/427bf4b' (2026-08-01)
• Updated input 'flake-parts/nixpkgs-lib':
    'github:nix-community/nixpkgs.lib/f590132' (2026-04-26)
  → 'github:nix-community/nixpkgs.lib/0e79af5' (2026-07-26)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/d233902' (2026-05-15)
  → 'github:nixos/nixpkgs/391b592' (2026-08-20)
• Updated input 'process-compose-flake':
    'github:Platonic-Systems/process-compose-flake/99bea96' (2026-01-08)
  → 'github:Platonic-Systems/process-compose-flake/464ff68' (2026-06-21)
• Updated input 'services-flake':
    'github:juspay/services-flake/b1965cb' (2026-05-17)
  → 'github:juspay/services-flake/4f56c8f' (2026-08-18)

Author: github-actions[bot]