deps: update flake.lock

[mrcjkb]

Automated changes by the update-flake-lock GitHub Action.

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/b1b43d32be000928cc71250ed77f4a0a5f2bc23a?narHash=sha256-8S9n69Dnpg8DhfFlP0YvMGmSOY2X4kImGSPWXYNpaHM%3D' (2025-02-16)
  → 'github:nixos/nixpkgs/dad564433178067be1fbdfcce23b546254b6d641?narHash=sha256-vn285HxnnlHLWnv59Og7muqECNMS33mWLM14soFIv2g%3D' (2025-02-20)

Running GitHub Actions on this PR

GitHub Actions will not run workflows on pull requests which are opened by a GitHub Action.

To run GitHub Actions workflows on this PR, run:

git branch -D update_flake_lock_action
git fetch origin
git checkout update_flake_lock_action
git commit --amend --no-edit
git push origin update_flake_lock_action --force