feat: add stream for Gemini

[AAEE86]

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Fixes #8652

Type of Change

• Bug fix (non-breaking change which fixes an issue)
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• Dependency upgrade

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• Test A
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[CXwudi]

@AAEE86 Is it my issue that I am getting this error

[AAEE86]

@CXwudi 在config_kwargs中设置

config_kwargs.pop("stream", None)

虽然能解决报错问题，但是仍然不是流模式，代码_handle_generate_stream_response似乎有问题