style: enforcing mypy typing for connectors (#9824)

Co-authored-by: John Bodley <john.bodley@airbnb.com>

superset/errors.py

@@ -15,10 +15,11 @@
 # specific language governing permissions and limitations
 # under the License.
 # pylint: disable=too-few-public-methods,invalid-name
-from dataclasses import dataclass
 from enum import Enum
 from typing import Any, Dict, Optional
 
+from dataclasses import dataclass
+
 
 class SupersetErrorType(str, Enum):
     """