flake.lock: Update (#505)

Flake lock file updates:

• Updated input 'neovim-nightly':
    'github:nix-community/neovim-nightly-overlay/ccadf4fb5be63e92b3559b361a6fb0638b2be71c?narHash=sha256-ssIPmQe/y7SbihUERqGimFwcw1A8lOq2ry9uNw%2BMBiA%3D' (2025-02-26)
  → 'github:nix-community/neovim-nightly-overlay/9def1919ea4ca5c16022845ccd57060bd22b6ff5?narHash=sha256-Zzs8LEZhYAGQkcYc8rvvyinE7KqMEtzb9X8Lkja1Y8E%3D' (2025-02-28)
• Updated input 'neovim-nightly/neovim-src':
    'github:neovim/neovim/23f7e5593db2b4c2d6c1a17de8497a653b4826e3?narHash=sha256-tv2PC7nxLNxMuV%2BzR%2B0slfSWKFMWcdSg5/i4knqoQik%3D' (2025-02-25)
  → 'github:neovim/neovim/3eee6f9d631b6c220564ef792c542964ed5e1cb9?narHash=sha256-Cj0l7WAMnI%2BEImtKqE0r4Aj14vZOBcTk8pnbBbUPsSY%3D' (2025-02-27)
• Updated input 'neovim-nightly/nixpkgs':
    'github:NixOS/nixpkgs/d9b69c3ec2a2e2e971c534065bdd53374bd68b97?narHash=sha256-ATMHHrg3sG1KgpQA5x8I%2BzcYpp5Sf17FaFj/fN%2B8OoQ%3D' (2025-02-24)
  → 'github:NixOS/nixpkgs/3a05eebede89661660945da1f151959900903b6a?narHash=sha256-Ly2fBL1LscV%2BKyCqPRufUBuiw%2BzmWrlJzpWOWbahplg%3D' (2025-02-26)

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

Author: mrcjkb