Bump langsmith in /ai/gen-ai-agents/custom-rag-agent/files

Bumps [langsmith](https://github.com/langchain-ai/langsmith-sdk) from 0.4.4 to 0.7.31.
- [Release notes](https://github.com/langchain-ai/langsmith-sdk/releases)
- [Commits](langchain-ai/langsmith-sdk@v0.4.4...v0.7.31)

---
updated-dependencies:
- dependency-name: langsmith
  dependency-version: 0.7.31
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

ai/gen-ai-agents/custom-rag-agent/files/requirements.txt

@@ -97,7 +97,7 @@ langgraph==0.5.0
 langgraph-checkpoint==3.0.0
 langgraph-prebuilt==0.5.1
 langgraph-sdk==0.1.55
-langsmith==0.4.4
+langsmith==0.7.31
 lxml==6.0.0
 markdown-it-py==3.0.0
 MarkupSafe==3.0.2