flake.lock: Update

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/3717a9f4981495d5487642554343acfacf4e64fa?narHash=sha256-b7j/GL7Pvmx9zpGnqjDzrTtLZktipsZSHJyMrLRQRKU%3D' (2024-07-27)
  → 'github:nix-community/fenix/6e4233dc54850e8aff6eff401400e9a9343881eb?narHash=sha256-7ehq0nfRHpU3oNAkRpklaDxQZUpuaUig2sR2LI%2BIL/U%3D' (2024-08-15)
• Updated input 'fenix/nixpkgs':
    'github:nixos/nixpkgs/5ad6a14c6bf098e98800b091668718c336effc95?narHash=sha256-Sb1jlyRO%2BN8jBXEX9Pg9Z1Qb8Bw9QyOgLDNMEpmjZ2M%3D' (2024-07-25)
  → 'github:nixos/nixpkgs/a58bc8ad779655e790115244571758e8de055e3d?narHash=sha256-dFZRVSgmJkyM0bkPpaYRtG/kRMRTorUIDj8BxoOt1T4%3D' (2024-08-11)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/aae54dde8c384acc310455504c9d8909646e0778?narHash=sha256-RenI%2B4lnrMH0DFLU4HlgCZ9X5yadeishI5Liy2XqNOQ%3D' (2024-07-26)
  → 'github:rust-lang/rust-analyzer/64a140527b383e3a2fe95908881624fc5374c60c?narHash=sha256-AT6K9JREduWC1zcIJIx8JTZa4sYZD6VvyB/xRnjphqY%3D' (2024-08-14)