flake: update inputs (#373)

Flake lock file updates:

• Updated input 'nixpkgs-stable':
    'github:NixOS/nixpkgs/759537f06e6999e141588ff1c9be7f3a5c060106?narHash=sha256-KQPI8CTTnB9CrJ7LrmLC4VWbKZfljEPBXOFGZFRpxao%3D' (2024-09-25)
  → 'github:NixOS/nixpkgs/fbca5e745367ae7632731639de5c21f29c8744ed?narHash=sha256-40J9tW7Y794J7Uw4GwcAKlMxlX2xISBl6IBigo83ih8%3D' (2024-09-28)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/76f0a61e733259e1034dd6523e039d04932ffefc?narHash=sha256-kZCiYpQJBZ3kL9QymS88mCxpQwqo8KqvZeHk6LATuY8%3D' (2024-09-27)
  → 'github:oxalica/rust-overlay/11a13e50debafae4ae802f1d6b8585101516dd93?narHash=sha256-OrrPiNBiikv9BR464XTT75FzOq7tKAvMbMi7YOKVIeg%3D' (2024-09-28)

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