[FEATURE]Replace serializer algorithm to dragon box

### 请描述您的需求或者改进建议
*对您想要需求或建议的清晰简洁的描述。*
Use dragonbox algorithm to optimize the conversation from a number to a string

### 请描述你建议的实现方案
*对您想要需求或建议的实现方案的详细描述。*
C++ implementation:
https://github.com/jk-jeon/dragonbox

### 描述您考虑过的替代方案
*对您考虑过的任何替代解决方案或功能的描述。*

#### 附加信息
*如果你还有其他需要提供的信息，可以在这里填写（可以提供截图、视频等）。*

Review the requested Dragonbox implementation at https://github.com/jk-jeon/dragonbox and inspect fastjson2's number-to-string serialization path. Identify the relevant serializer entry point and existing performance tests before determining how completion should be measured; the issue names no files or tests.

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