Made pythonize much faster by replacing serde_json with sonic_rs

Used [sonic_rs](https://github.com/cloudwego/sonic-rs) which is much faster than `serde_json`. check out the [https://github.com/cloudwego/sonic-rs?tab=readme-ov-file#benchmark](benchmark) for more information. I've also followed all the rules for the migration from [here](https://github.com/cloudwego/sonic-rs/blob/main/docs/serdejson_compatibility.md) .