Raise the final exception when all retries of Shopify request has failed

(grafted from b0fef2fdbe01bb7a7fc4f7d6032b9ab6ef61160c)

--HG--
branch : 8.0

modules/web_shop_shopify/tests/tools.py

@@ -19,6 +19,7 @@ def retry(func):
                 return func(*args, **kwargs)
             except Exception:
                 time.sleep(1)
+        return func(*args, **kwargs)
     return wrapper