Use Python 3.9

Author: Flamefire

.github/workflows/synchronize-launchpad.yml

@@ -15,9 +15,10 @@ jobs:
     steps:
       - uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
+          python-version: '3.9'
       - name: Install dependencies
         run: |
+          python -V
           venv_dir="/tmp/venv"
           python -m venv "$venv_dir"
           . $venv_dir/bin/activate