chore: bump langchain-text-splitters in /libs/rag-core-api

Bumps [langchain-text-splitters](https://github.com/langchain-ai/langchain) from 1.1.0 to 1.1.2.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@langchain-text-splitters==1.1.0...langchain-text-splitters==1.1.2)

---
updated-dependencies:
- dependency-name: langchain-text-splitters
  dependency-version: 1.1.2
  dependency-type: direct:production
...

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Author: dependabot[bot]