Added tag for 2025-09-01 in readme file

Author: fmabroukmsft

specification/machinelearningservices/resource-manager/readme.md

@@ -27,7 +27,20 @@ These are the global settings for the Machine Learning Services API.
 
 ``` yaml
 openapi-type: arm
-tag: package-preview-2025-07
+tag: package-2025-09-01
+```
+
+### Tag: package-2025-09-01
+
+These settings apply only when `--tag=package-2025-09-01` is specified on the command line.
+
+```yaml $(tag) == 'package-2025-09-01'
+input-file:
+  - Microsoft.MachineLearningServices/stable/2025-09-01/machineLearningServices.json
+  - Microsoft.MachineLearningServices/stable/2025-09-01/mfe.json
+  - Microsoft.MachineLearningServices/stable/2025-09-01/registries.json
+  - Microsoft.MachineLearningServices/stable/2025-09-01/workspaceFeatures.json
+  - Microsoft.MachineLearningServices/stable/2025-09-01/workspaceRP.json
 ```
 
 ### Tag: package-preview-2025-07