Interface AzureFunctionsAuthentication

To protect your Azure Function, set its authLevel to function and provide the function's key to be used inside the x-functions-key header. For more information, see the Azure Functions documentation.

To protect the secret key from being exposed, remove the code parameter and secret key from the URL. For example, use `https://foo.azurewebsites.net/api/bar` instead of
`https://foo.azurewebsites.net/api/bar?code=secret`.