chore(deps): bump undici and @llamaindex/readers

Removes [undici](https://github.com/nodejs/undici). It's no longer used after updating ancestor dependency [@llamaindex/readers](https://github.com/run-llama/LlamaIndexTS/tree/HEAD/packages/readers). These dependencies need to be updated together.


Removes `undici`

Updates `@llamaindex/readers` from 2.0.8 to 3.1.3
- [Release notes](https://github.com/run-llama/LlamaIndexTS/releases)
- [Changelog](https://github.com/run-llama/LlamaIndexTS/blob/main/packages/readers/CHANGELOG.md)
- [Commits](https://github.com/run-llama/LlamaIndexTS/commits/@llamaindex/readers@3.1.3/packages/readers)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 
  dependency-type: indirect
- dependency-name: "@llamaindex/readers"
  dependency-version: 3.1.3
  dependency-type: direct:production
...

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Author: dependabot[bot]