1. Fix bug which costs twice gpu memory (Thanks to [@suc16](https://github.com/suc16) and [@myml](https://github.com/myml)).
2. Add gpu memory clear function after each call of ChatGLM.
3. Add `nghuyong/ernie-3.0-nano-zh` and `nghuyong/ernie-3.0-base-zh` as Embedding model alternatives，costing less gpu than `GanymedeNil/text2vec-large-chinese` (Thanks to [@ywancit](https://github.com/ywancit))
3. Add `nghuyong/ernie-3.0-nano-zh` and `nghuyong/ernie-3.0-base-zh` as Embedding model alternatives，costing less gpu than `GanymedeNil/text2vec-large-chinese` (Thanks to [@lastrei](https://github.com/lastrei))
