Paddle Toolkit Development Competition No.4】 Paddle 适配 torch-scatter

[LitLeo]

赛题要求的是“尽量使用 paddle.geometric 下的基础 python API 等价组合实现上述公开 API 的功能”。跟我的实现方案是两个不同的方向，需要麻烦官方考量我的方案是否可以。可以我就继续做下去，不可以就算了。

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[HydrogenSulfate]

感谢提交PR，推荐使用paddle.geometric下的API是因为这些希望尽量减少开发量（如果能完全等价实现的话），但是也允许基于原来的C++算子进行开发。RFC本身没有问题。

[HydrogenSulfate]

LGTM

[HydrogenSulfate]

@LitLeo 可以签署一下这个CLA协议：