docs: langchain v3 integration tutorial (#1818)

- This PR adds a integration tutorial for evaluating a simple
question-answering bot using LangChain.
- fixed the make file

Author: sahusiddharth

Makefile

@@ -39,7 +39,7 @@ run-ci: format lint type test ## Running all CI checks
 build-docsite: ## Use GPT4 to rewrite the documentation
 	@echo "convert ipynb notebooks to md files"
 	$(Q)python $(GIT_ROOT)/docs/ipynb_to_md.py
-	@(Q)mkdocs build
+	$(Q)mkdocs build
 serve-docsite: ## Build and serve documentation
 	$(Q)mkdocs serve --dirtyreload
 

docs/howtos/integrations/_langchain.md

@@ -8,7 +8,7 @@ happy to look into it 🙂
 
 ## Frameworks
 
-- [Langchain](./_langchain.md) - Langchain is a framework for building LLM applications, more information can be found [here](https://www.langchain.com/).
+- [Langchain](./langchain.md) - Langchain is a framework for building LLM applications, more information can be found [here](https://www.langchain.com/).
 - [LlamaIndex](./_llamaindex.md) - LlamaIndex is a framework for building RAG applications, more information can be found [here](https://www.llamaindex.ai/).
 
 ## Tracing Tools