rollback langchain

requirements.txt

@@ -1,11 +1,11 @@
 anthropic==0.3.11
 faiss-cpu==1.7.4
-langchain==0.0.301
+langchain==0.0.300 # rolling back update to avoid a bug in langchain's chatanthropic
 langsmith==0.0.40
+numpy>=1.22.2 # not directly required, pinned by Snyk to avoid a vulnerability
 openai==0.28.0
 pypdf==3.16.2
 streamlit==1.27.0
 streamlit-feedback==0.1.2
 tiktoken==0.5.1
-numpy>=1.22.2 # not directly required, pinned by Snyk to avoid a vulnerability
 tornado>=6.3.3 # not directly required, pinned by Snyk to avoid a vulnerability