Update readme

Author: johnkoh-msft

specification/azuredatatransfer/resource-manager/readme.md

@@ -29,7 +29,16 @@ These are the global settings for the azuredatatransfer.
 ``` yaml
 openapi-type: arm
 openapi-subtype: rpaas
-tag: package-2025-10-10-preview
+tag: package-2026-02-06-preview
+```
+
+### Tag: package-2026-02-06-preview
+
+These settings apply only when `--tag=package-2026-02-06-preview` is specified on the command line.
+
+```yaml $(tag) == 'package-2026-02-06-preview'
+input-file:
+  - Microsoft.AzureDataTransfer/preview/2026-02-06-preview/azuredatatransfer.json
 ```
 
 ### Tag: package-2025-10-10-preview