Better testing error messages on protocol errors.

sanic/testing.py

@@ -40,6 +40,9 @@ class SanicTestClient:
                     response = await getattr(session, method.lower())(
                         url, verify=False, *args, **kwargs
                     )
+                except httpx.exceptions.ConnectionClosed:
+                    logger.error(f"{method.upper()} {url} broken HTTP, response is None!")
+                    return None
                 except NameError:
                     raise Exception(response.status_code)