chore(deps): update dependency langchain to v1.1.0 (googleapis#2022)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [langchain](https://redirect.github.com/langchain-ai/langchain)
([source](https://redirect.github.com/langchain-ai/langchain/tree/HEAD/libs/langchain),
[changelog](https://redirect.github.com/langchain-ai/langchain/releases?q=tag%3A%22langchain%3D%3D1%22))
| `==1.0.8` -> `==1.1.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/langchain/1.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/langchain/1.0.8/1.1.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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Author: renovate-bot

docs/en/getting-started/quickstart/python/langchain/requirements.txt

@@ -1,4 +1,4 @@
-langchain==1.0.8
+langchain==1.1.0
 langchain-google-vertexai==3.1.0
 langgraph==1.0.3
 toolbox-langchain==0.5.3