feat: test: add coverage for add_extra_session_options

[n24q02m]

🎯 What:
Added unit tests for add_extra_session_options in qwen3_embed/common/onnx_model.py which was missing test coverage.

📊 Coverage:

• Tested valid paths (mutating enable_cpu_mem_arena to True and False).
• Tested error paths (raising ValueError when an invalid option is provided).

✨ Result:
Improved test coverage and safety for the OnnxModel option configuration logic.

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PR created automatically by Jules for task 17211056917102681007 started by @n24q02m

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[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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