Bump onnx in /mistralai-Mistral-7B-Instruct-v0.3/VitisAI

Bumps [onnx](https://github.com/onnx/onnx) from 1.18.0 to 1.21.0.
- [Release notes](https://github.com/onnx/onnx/releases)
- [Changelog](https://github.com/onnx/onnx/blob/main/docs/Changelog-ml.md)
- [Commits](onnx/onnx@v1.18.0...v1.21.0)

---
updated-dependencies:
- dependency-name: onnx
  dependency-version: 1.21.0
  dependency-type: direct:production
...

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Author: dependabot[bot]

mistralai-Mistral-7B-Instruct-v0.3/VitisAI/requirements_vitisai_llm.txt

@@ -17,7 +17,7 @@ nltk
 numpy
 
 # Pin onnx version
-onnx==1.18.0
+onnx==1.21.0
 onnxruntime==1.21.1
 onnxruntime-genai==0.7.1
 optimum