Merge pull request #174 from stackql/feature/doc-updates

updated azure

Author: jeffreyaven

docs/azure-docs/index.md

@@ -49,9 +49,13 @@ REGISTRY PULL azure;
 
 ## Authentication
 
-
 StackQL uses Azure application credentials obtained using the <CopyableCode code="az login" /> command from the Azure SDK.  For more information, see <a href="https://learn.microsoft.com/en-us/cli/azure/authenticate-azure-cli">here</a>.
 
+### Authenticating using an Azure Service Principal
+
+To authenticate using an Azure Service Principal, set the following environment variables: <CopyableCode code="AZURE_TENANT_ID" />, <CopyableCode code="AZURE_CLIENT_ID" /> and <CopyableCode code="AZURE_CLIENT_SECRET" />, see [__creating-an-azure-service-principal__](https://learn.microsoft.com/en-us/azure/developer/go/azure-sdk-authentication-service-principal?tabs=azure-cli#2-create-an-azure-service-principal).
+
+
 ## Services
 <div class="row">
 <div class="providerDocColumn">