[Bugfix] Don't log OpenAI field aliases as ignored

[mgoin]

FIX #11363

This issue was found because we use an alias for schema in JsonSchemaResponseFormat due to conflicts with pydantic:

class JsonSchemaResponseFormat(OpenAIBaseModel):
    name: str
    description: Optional[str] = None
    # schema is the field in openai but that causes conflicts with pydantic so
    # instead use json_schema with an alias
    json_schema: Optional[Dict[str, Any]] = Field(default=None, alias='schema')
    strict: Optional[bool] = None

Our logging for unused fields in requests was not taking into account aliases, so we were incorrectly reporting that fields were being ignored

WARNING 12-20 16:05:31 protocol.py:52] The following fields were present in the request but ignored: {'schema'}

[github-actions]

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[DarkLight1337]

Thanks for fixing!