fix(base_client): max_retries null point exception

[aniaan]

Reproduce code(Due to various reasons, the api request failed, such as rate limiting.):

resp = co.tokenize(text=text, model="embed-multilingual-light-v3.0", offline=False)

Exception stack trace:

response = self.httpx_client.request(*args, **kwargs)
     95 if _should_retry(response=response):
---> 96     if max_retries > retries:
     97         time.sleep(_retry_timeout(response=response, retries=retries))
     98         return self.request(max_retries=max_retries, retries=retries + 1, *args, **kwargs)

TypeError: '>' not supported between instances of 'NoneType' and 'int'

The reason is because of None value for max_retries.

Other similar codes should also have corresponding issues, so I made some modifications together.

[CLAassistant]

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