replace openai-edge with openai

[hayawata3626]

Since the openai library has been using fetch since v4, I think it would be better to use openai version 4 without the need for openai-edge.

If it is not needed, I will close this.

ref: https://github.com/dan-kwiat/openai-edge#openai-edge

Update July 2023: The official openai library will use fetch in v4, hopefully making openai-edge redundant. You can try it in beta now, more info here: https://github.com/openai/openai-node/discussions/182