added langchain version restriction for test

uncommented the requirements pip install in Dockerfile

.devcontainer/Dockerfile

@@ -12,4 +12,4 @@ FROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}
 #COPY library-scripts/github-debian.sh /tmp/library-scripts/
 RUN apt-get update && apt-get update
 RUN pip install --upgrade pip
-#RUN pip install -r requirements.txt
+RUN pip install -r requirements.txt

requirements.txt

@@ -1,7 +1,7 @@
 huggingface_hub
 chromadb
 faiss-cpu
-langchain < 0.2.0
+langchain==0.1.5
 langchain-community
 python-dotenv
 bs4