Issue with test_gemini_chat (gemini_test.GeminiModelWrapperTest)

[zyzhang1130]

It seems the current test_gemini_chat (gemini_test.GeminiModelWrapperTest) is not compatible with response.candidates, and I got the following error in pr Gemini chat wrapper fix due to this reason.:

ERROR: test_gemini_chat (gemini_test.GeminiModelWrapperTest)
Test for chat API.
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Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/unittest/mock.py", line 1336, in patched
    return func(*newargs, **newkeywargs)
  File "/home/runner/work/agentscope/agentscope/tests/gemini_test.py", line 62, in test_gemini_chat
    response = model(contents="Hi!")
  File "/home/runner/work/agentscope/agentscope/src/agentscope/models/model.py", line 117, in checking_wrapper
    return model_call(self, *args, **kwargs)
  File "/home/runner/work/agentscope/agentscope/src/agentscope/models/gemini_model.py", line 153, in __call__
    if response.candidates:
AttributeError: 'DummyResponse' object has no attribute 'candidates'

However, I think response.candidates is essential for error handling in the event that response returned from API does not contain any text (see the pr Gemini chat wrapper fix for details).

[DavdGao]

Thanks for your report, and we will fix this bug as soon as possible.