Support Azure serverless deployment for Cohere model

[sgjsakura]

Currently Azure AI Hub (ai.azure.com) supports serverless Cohere model on Azure cloud service, the endpoint for these deployments are similar with OpenAI Azure Service. This package does not support use custom API endpoint URL cohere. Please kindly give support for this situation and many thanks.

[lofcz]

Support for Azure Cohere will be added in version 3.1