Azure secret doc enhancement (#23079)

* * azure secret doc enhancement
Co-authored-by: Sarah Chavis <62406755+schavis@users.noreply.github.com>

---------

Co-authored-by: Sarah Chavis <62406755+schavis@users.noreply.github.com>

website/content/docs/secrets/azure.mdx

@@ -23,6 +23,15 @@ The password will be deleted when the lease is revoked.
 
 ## Setup
 
+<Note>
+
+  You can configure the Azure secrets engine with the Vault API or
+  established environment variables such as `AZURE_CLIENT_ID` or
+  `AZURE_CLIENT_SECRET`. If you use both methods, note that
+  environment variables always take precedence over API values.
+
+</Note>
+
 Most secrets engines must be configured in advance before they can perform their
 functions. These steps are usually completed by an operator or configuration
 management tool.