flake.lock: Update

Flake lock file updates:

• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/914a1caab54e48a028b2407d0fe6fade89532f67?narHash=sha256-TBujPMMIv8RG6BKlsBEpCln1ePmWz79xTcJOQpU2L18%3D' (2024-08-31)
  → 'github:rust-lang/rust-analyzer/94b526fc86eaa0e90fb4d54a5ba6313aa1e9b269?narHash=sha256-nCmG4NJpwI0IoIlYlwtDwVA49yuspA2E6OhfCOmiArQ%3D' (2024-09-15)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/345c263f2f53a3710abe117f28a5cb86d0ba4059?narHash=sha256-sjiGsMh%2B1cWXb53Tecsm4skyFNag33GPbVgCdfj3n9I%3D' (2024-09-13)
  → 'github:NixOS/nixpkgs/99dc8785f6a0adac95f5e2ab05cc2e1bf666d172?narHash=sha256-gI9kkaH0ZjakJOKrdjaI/VbaMEo9qBbSUl93DnU7f4c%3D' (2024-09-16)
• Updated input 'rycee':
    'gitlab:rycee/nur-expressions/fdc18b96e954599a613fd3c0b4bba3a07ff9148d?narHash=sha256-0xnxwwn3Nfdt%2BHWjCm6ZASfnuAKQatofwjKJlRzUl8I%3D' (2024-09-12)
  → 'gitlab:rycee/nur-expressions/889bc28278f62d16ff47db83029d666213f9e311?narHash=sha256-yiqv3itGgoVgcwrlnrhMqqafUbTWw0NKfN%2B9%2BEoOr5c%3D' (2024-09-17)