flake.lock: Update (#682)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/4f807e8940284ad7925ebd0a0993d2a1791acb2f?narHash=sha256-IiA3jfbR7K/B5%2B9byVi9BZGWTD4VSbWe8VLpp9B/iYk%3D' (2024-09-11)
  → 'github:NixOS/nixpkgs/c04d5652cfa9742b1d519688f65d1bbccea9eb7e?narHash=sha256-PmUr/2GQGvFTIJ6/Tvsins7Q43KTMvMFhvG6oaYK%2BWk%3D' (2024-09-19)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/e9f8641c92f26fd1e076e705edb12147c384171d?narHash=sha256-YfLRPlFZWrT2oRLNAoqf7G3%2BNnUTDdlIJk6tmBU7kXM%3D' (2024-09-14)
  → 'github:oxalica/rust-overlay/a66e16cb21e4428224925dbf1b66238c727dda0a?narHash=sha256-wrXknshJMRLv91KQD5d7ovUqJ70FlDM7XeG/upSsKgM%3D' (2024-09-21)

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