fix: mypy

api/core/plugin/entities/plugin_daemon.py

@@ -185,11 +185,8 @@ class PluginOAuthCredentialsResponse(BaseModel):
     metadata: Mapping[str, Any] = Field(
         default_factory=dict, description="The metadata of the OAuth, like avatar url, name, etc."
     )
-    expires_at: int | None = Field(description="The expires at time of the credentials. UTC timestamp.")
+    expires_at: int = Field(default=-1, description="The expires at time of the credentials. UTC timestamp.")
     credentials: Mapping[str, Any] = Field(description="The credentials of the OAuth.")
-    expires_at: int = Field(
-        default=-1, description="The timestamp of the credentials expires at, -1 means never expires."
-    )
 
 
 class PluginListResponse(BaseModel):