Add tox

Signed-off-by: Ching Yi, Chan <[email protected]>

.github/workflows/tox.yaml

@@ -26,6 +26,7 @@ jobs:
           python -m pip install --upgrade pip
           if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
           pip install -e '.[duckdb]'
+          pip install tox
       - name: Run tox-sqlalchemy
         run: tox -c tox-sqlalchemy.ini
       - name: Run tox-ruamel