[Bug]: Undefined array key "usage" with Vision endpoint on Azure

Description

I'm trying to use vision on Azure, this was working before.

It seems that Azure has changed the format of their response for the Vision endpoint.

I am creating the client with the factory etc. But since today the code that had been working has stopped working.
This results in the error Undefined array key "usage"
I'm running the latests version of the client.

Steps To Reproduce

         $baseUri = 'https://tellet-azure-sweden.openai.azure.com/openai/deployments/tellet-gpt-4-vision-preview';
        
        $client = OpenAI::factory()
        ->withBaseUri($baseUri)
        ->withHttpClient(new \GuzzleHttp\Client(['timeout' => 300, 'connect_timeout' => 300]))
        ->withHttpHeader('api-key', $apiKey)
        ->withQueryParam('api-version', '2023-12-01-preview')
        ->make();
        
         $base64Image = $this->imageToBase64($image);
         $encoded = 'data:image/jpeg;base64,'.$base64Image;

    $imageArray[] = [
        'type' => 'text',
        'text' => 'Analyse this photograph and provide a detailed description of its contents. Focus on identifying and listing all visible items, with particular attention to food items present. '
    ];
    
    $imageArray[] = [
        'type' => 'image_url',
        'image_url' => ['url' => $encoded]
    ];

    $messagesArray = array();
    $messagesArray[] = [
        'role' => 'user',
        'content' => $imageArray
    ];
    
    $settings['messages'] = $messagesArray;
    $settings['max_tokens'] = 1200;
    $settings['messages'] = $messagesArray;
    $response = $client->chat()->create($settings);

OpenAI PHP Client Version

v0.8.4

PHP Version

8.1

Notes

No response

Start at the chat()->create entry point and reproduce the request against the Azure Vision endpoint using the configuration and image payload in the issue. Inspect where the response's usage field is accessed; done means the documented Azure response format no longer causes an undefined array key error, with a regression test if the existing test structure identifies a suitable location.