fix: The type in OpenAIChatCompletionChoiceMessageContentItemModel.im…

[zmhu]

The type in OpenAIChatCompletionChoiceMessageContentItemModel.imageUrl() should be "image_url".

api docs: https://platform.openai.com/docs/api-reference/chat/create

curl https://api.openai.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -d '{
    "model": "gpt-4-vision-preview",
    "messages": [
      {
        "role": "user",
        "content": [
          {
            "type": "text",
            "text": "What’s in this image?"
          },
          {
            "type": "image_url",
            "image_url": {
              "url": "https://upload.wikimedia.org/wikipedia/commons/thumb/d/dd/Gfp-wisconsin-madison-the-nature-boardwalk.jpg/2560px-Gfp-wisconsin-madison-the-nature-boardwalk.jpg"
            }
          }
        ]
      }
    ],
    "max_tokens": 300
  }'

[marc-wilson]

@zmhu @anasfik can we merge this? Can't get anything to work with imageUrl so I'm assuming this is the fix.

[anasfik]

Thank you, this is merged.