flake.lock: Update

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/24002092be13b2efe87700229d143b0d1eaa5d12' (2024-03-09)
  → 'github:nix-community/fenix/a4b7a4acfb44ee78785b0b53667066a9b1e32245' (2024-05-18)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/2397e7a887252aa995d3790164b34b6c76ed94b4' (2024-03-08)
  → 'github:rust-lang/rust-analyzer/83ba42043166948db91fcfcfe30e0b7eac10b3d5' (2024-05-16)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/0e7f98a5f30166cbed344569426850b21e4091d4' (2024-03-09)
  → 'github:NixOS/nixpkgs/02923630b89aa1ab36ef8e422501a6f4fd4b2016' (2024-05-18)
• Updated input 'utils':
    'github:numtide/flake-utils/d465f4819400de7c8d874d50b982301f28a84605' (2024-02-28)
  → 'github:numtide/flake-utils/b1d9ab70662946ef0850d488da1c9019f3a9752a' (2024-03-11)