fix --model_path argument in api_server.py

[PascalSalesch]

If you pass a --model_path to api_server.py that you haven't downloaded already, it won't be able to resolve because the subfolder in api_server.py doesn't exist: subfolder='hunyuan3d-dit-v2-mini-turbo'

https://huggingface.co/tencent/Hunyuan3D-2/tree/main

there's currently no way to pass a subfolder to api_server.py via args. After the change you can call

    python3 api_server.py \
        --host 0.0.0.0 \
        --port 8080 \
        --enable_tex \
        --model_path tencent/Hunyuan3D-2 \
+       --subfolder hunyuan3d-dit-v2-0-turbo \
        --tex_model_path tencent/Hunyuan3D-2

as you can see I changed subfolder from hunyuan3d-dit-v2-mini-turbo to hunyuan3d-dit-v2-0-turbo

[tencent-adm]

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[PascalSalesch]

https://github.com/Tencent-Hunyuan/Hunyuan3D-2/issues/71#issuecomment-3462253772