Cache Python pip packages when venv is used

Author: JohT

.github/workflows/public-analyze-code-graph.yml

@@ -125,6 +125,7 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python }}
+          cache: 'pip'
 
       - name: (Python Setup) Conda environment info
         if: inputs.use-venv_virtual_python_environment == 'false'