flake.lock: Update (#309)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/2c7f3c0fb7c08a0814627611d9d7d45ab6d75335' (2023-12-04)
  → 'github:NixOS/nixpkgs/bd645e8668ec6612439a9ee7e71f7eac4099d4f6' (2024-01-02)
• Updated input 'pre-commit-hooks':
    'github:cachix/pre-commit-hooks.nix/e5ee5c5f3844550c01d2131096c7271cec5e9b78' (2023-11-25)
  → 'github:cachix/pre-commit-hooks.nix/9d3d7e18c6bc4473d7520200d4ddab12f8402d38' (2023-12-30)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/2cfb76b8e836a26efecd9f853bea78355a11c58a' (2023-12-09)
  → 'github:oxalica/rust-overlay/a127cccf7943beae944953963ba118d643299c3b' (2024-01-06)

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Rok Garbas <[email protected]>