[`Doc`] update model doc qwen2 (#29238)
* update model doc qwen2
* Update docs/source/en/model_doc/qwen2.md
Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com>
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Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com>
