Add the ability to authenticate to Azure OpenAI using either OpenAI API key or Azure AD Workload Identity

[pauldotyu]

Is your feature request related to a problem? Please describe.
When deploying this demo using Azure OpenAI service, putting the OpenAI API key in a configMap, secret, or even worse environment variable is not ideal.

Describe the solution you'd like
Being able to authenticate to Azure OpenAI using a managed identity and Azure AD Workload Identity is a better way. No need to store any credentials in the Kubernetes cluster.

Describe alternatives you've considered
N/A

Additional context
N/A

[pauldotyu]

Resolved with PR#60