fix: support openai o1 model with custom model name.

[Mai0313]

Why are these changes needed?

For my company, MediaTek, we use custom name called aide-o1-preview and aide-o1-mini for o1 and o1-mini via Azure Service.
I know using "o1-" in model_name to detect o1 model can be bad, but as far as I know, only OpenAI o1 model contains o1- and it perfectly solve my problem.

I am open to discuss more about how to fix it better.

Related issue number

#347

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[davorrunje]

@Mai0313 I understand the need to fix this but I would suggest a slightly different approach. For api_type=="azure", we could add an additional field oai_model_name that could be set to the original OAI name. That would be easier to scale and maintain.

We plan to release 0.7.2 on Wednesday so we have enough time to make this change for the next release.