[BUG FIX] fix memory leak for ort backend

[ChaoII]

fix memory leak for ort backend #2414

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✅ ChaoII
❌ Jiang-Jia-Jun
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[Jiang-Jia-Jun]

@ChaoII 这里修复的内存泄露问题是指读入的模型buffer吗？

[ChaoII]

@ChaoII 这里修复的内存泄露问题是指读入的模型buffer吗？

是的。