overriding model property with more specific object type doesn't work

Describe the bug
When an object schema derives from another object schema using allOf, and redeclares a property that had an object type to use a different object type, the generated code uses the old type for that property.

OpenAPI Spec File
https://gist.github.com/eli-bl/d5658d6714e1c9ef544ef1fc8902960a

With this example, the type of SpecialTask.result in the generated code should be SpecialTaskOutputData. Instead it is being declared as BaseTaskResult, the same as BaseTask.result.

Desktop (please complete the following information):

• OS: macOS 14.5
• Python Version: 3.8.15
• openapi-python-client version: 0.21.5

首先使用報告中連結的 OpenAPI 規格重現問題，並檢查為 BaseTask 和 SpecialTask 產生的模型。追蹤繼承的和重新宣告的物件屬性如何解析；當 SpecialTask.result 以 SpecialTaskOutputData 型別而不是 BaseTaskResult 產生時，即表示完成。