Resolve dependency issues

[bloodeagle40234]

This commit includes fixes for a couple of following dependency issues

• fschat>=0.2.23

  • systemp_prompt variable, which is used in common.py, of Conversation class in fschat==0.2.20 is not available, >= 0.2.23 was required. (*1)
  • fschat==0.2.20 is incompatible with transformers==4.31.0 but >=0.2.23 is applicable.

• anthropic

  • common.py and gen_api_answer.py imports anthoropic but not appeared in requirements.txt yet.

Related to https://github.com/yuzu-ai/japanese-llm-ranking/issues/11

1: https://github.com/lm-sys/FastChat/commit/c1e38c3829b3e9609589c41e85201dc4730e00f2

[passaglia]

Sorry for taking a while to get to this, thanks a lot for the fix!