Update jekyll-gh-pages.yml

.github/workflows/jekyll-gh-pages.yml

@@ -42,7 +42,7 @@ jobs:
           python -m venv .venv                # Create a virtual environment
           source .venv/bin/activate           # Activate the virtual environment
           pip install --upgrade pip           # Upgrade pip in the virtual environment
-          pip install nbconvert               # Install nbconvert
+          pip install nbconvert pyyaml        # Install nbconvert and PyYAML (yaml module)
           # Add any other necessary package installations here
 
       - name: Execute conversion script