Implicit graphviz dependency

### Describe the bug Sadly repo involved is not public, so can't share. Had to add this in GitHub actions to make `..graphviz` directive work ```yml - name: Install Graphviz run: sudo apt-get update && sudo apt-get install -y graphviz ``` Suggests to me that there is a hidden dependency which we don't see ### How to Reproduce Create a repo with a graphviz graph. Build with github actions ### Environment Information ```text Github +3Lines changed: 3 additions & 0 deletions Original file line number Original file line Diff line number Diff line change # This workflow will build and deploy documentation to GitHub Pages name: Deploy documentation to GitHub Pages # Controls when the workflow will run on: # Triggers the workflow when develop is updated push: branches: ["main"] # Allows you to run this workflow manually from the Actions tab workflow_dispatch: # Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages permissions: contents: read pages: write id-token: write # Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued. # However, do NOT cancel in-progress runs as we want to allow these production deployments to complete. concurrency: group: "pages" cancel-in-progress: false # A workflow run is made up of one or more jobs that can run sequentially or in parallel jobs: # This workflow contains a single job called "build" build: # The type of runner that the job will run on runs-on: ubuntu-latest # Steps represent a sequence of tasks that will be executed as part of the job steps: # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it - uses: actions/checkout@v6 - name: Install uv and Set up Python uses: astral-sh/setup-uv@v7 with: python-version: "3.11" enable-cache: true - name: Install Graphviz run: sudo apt-get update && sudo apt-get install -y graphviz - name: Install dependencies from pyproject.toml run: | uv sync - name: Build documentation run: | uv run make clean html ``` ### Sphinx extensions ```python ``` ### Additional context _No response_