flake: update inputs (#337)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/4f807e8940284ad7925ebd0a0993d2a1791acb2f?narHash=sha256-IiA3jfbR7K/B5%2B9byVi9BZGWTD4VSbWe8VLpp9B/iYk%3D' (2024-09-11)
  → 'github:NixOS/nixpkgs/345c263f2f53a3710abe117f28a5cb86d0ba4059?narHash=sha256-sjiGsMh%2B1cWXb53Tecsm4skyFNag33GPbVgCdfj3n9I%3D' (2024-09-13)
• Updated input 'nixpkgs-stable':
    'github:NixOS/nixpkgs/e65aa8301ba4f0ab8cb98f944c14aa9da07394f8?narHash=sha256-PyFVySdGj3enKqm8RQuo4v1KLJLmNLOq2yYOHsI6e2Q%3D' (2024-09-11)
  → 'github:NixOS/nixpkgs/8f7492cce28977fbf8bd12c72af08b1f6c7c3e49?narHash=sha256-RuVXUwcYwaUeks6h3OLrEmg14z9aFXdWppTWPMTwdQw%3D' (2024-09-14)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/e9f8641c92f26fd1e076e705edb12147c384171d?narHash=sha256-YfLRPlFZWrT2oRLNAoqf7G3%2BNnUTDdlIJk6tmBU7kXM%3D' (2024-09-14)
  → 'github:oxalica/rust-overlay/ff13821613ffe5dbfeb4fe353b1f4bf291d831db?narHash=sha256-T7W%2BohiXe1IY0yf/PpS4wQItZ0SyRO%2B/v8kqNpMXlI4%3D' (2024-09-15)

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