flake: update inputs (#210)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/9f4128e00b0ae8ec65918efeba59db998750ead6?narHash=sha256-rwz8NJZV%2B387rnWpTYcXaRNvzUSnnF9aHONoJIYmiUQ%3D' (2024-07-03)
  → 'github:NixOS/nixpkgs/655a58a72a6601292512670343087c2d75d859c1?narHash=sha256-cPJoFPXU44GlhWg4pUk9oUPqurPlCFZ11ZQPk21GTPU%3D' (2024-07-08)
• Updated input 'nixpkgs-stable':
    'github:NixOS/nixpkgs/49ee0e94463abada1de470c9c07bfc12b36dcf40?narHash=sha256-WrDV0FPMVd2Sq9hkR5LNHudS3OSMmUrs90JUTN%2BMXpA%3D' (2024-07-06)
  → 'github:NixOS/nixpkgs/194846768975b7ad2c4988bdb82572c00222c0d7?narHash=sha256-NGKVY4PjzwAa4upkGtAMz1npHGoRzWotlSnVlqI40mo%3D' (2024-07-07)

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