chore(deps): update pip (#2258)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-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))
| `==1.2.0` → `==1.2.1` |
![age](https://developer.mend.io/api/mc/badges/age/pypi/langchain/1.2.1?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/langchain/1.2.0/1.2.1?slim=true)
|
|
[langchain-google-vertexai](https://redirect.github.com/langchain-ai/langchain-google)
([source](https://redirect.github.com/langchain-ai/langchain-google/tree/HEAD/libs/vertexai),
[changelog](https://redirect.github.com/langchain-ai/langchain-google/releases?q=%22vertexai%22))
| `==3.2.0` → `==3.2.1` |
![age](https://developer.mend.io/api/mc/badges/age/pypi/langchain-google-vertexai/3.2.1?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/langchain-google-vertexai/3.2.0/3.2.1?slim=true)
|

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

@@ -1,5 +1,5 @@
-langchain==1.2.0
-langchain-google-vertexai==3.2.0
+langchain==1.2.1
+langchain-google-vertexai==3.2.1
 langgraph==1.0.5
 toolbox-langchain==0.5.4
 pytest==9.0.2