fix: remove the unused retry index field (#11903)

Signed-off-by: -LAN- <laipz8200@outlook.com>
Co-authored-by: Novice Lee <novicelee@NoviPro.local>
Co-authored-by: -LAN- <laipz8200@outlook.com>

api/models/model.py

@@ -4,7 +4,7 @@ import uuid
 from collections.abc import Mapping
 from datetime import datetime
 from enum import Enum, StrEnum
-from typing import Any, Literal, Optional
+from typing import TYPE_CHECKING, Any, Literal, Optional
 
 import sqlalchemy as sa
 from flask import request
@@ -24,6 +24,9 @@ from .account import Account, Tenant
 from .engine import db
 from .types import StringUUID
 
+if TYPE_CHECKING:
+    from .workflow import Workflow
+
 
 class DifySetup(db.Model):
     __tablename__ = "dify_setups"