Allow setting query transformers in the BaseRAGQA

[berkecanrizai]

There are already set of prompts such as prompt_query_rewrite and prompt_query_rewrite_hyde, allow setting the query transformation behaviour in the BaseRAGQA initialization. It can default to None to skip it.

[harshit240205]

@berkecanrizai Can I work on this issue ?

[szymondudycz]

@harshit240205 Sure, feel free to work on this issue if you are interested

[Ch-Abhinav-Chowdary]

Can I work on the issue

[szymondudycz]

Can I work on the issue

Yes, feel free to work on it

[Ch-Abhinav-Chowdary]

I’ve opened a PR for this issue: #145 . Please review.