fix connecting

tests/test_saving_related.py

@@ -46,6 +46,8 @@ def create_test_database():
 
 @pytest.mark.asyncio
 async def test_model_relationship():
+    async with db:
+        async with db.transaction(force_rollback=True):
             cat = await Category(name="Foo", code=123).save()
             ws = await Workshop(topic="Topic 1", category=cat).save()