added blob readme (#28246)

Author: tasherif-msft

specification/storage/data-plane/Microsoft.BlobStorage/readme.md

@@ -25,7 +25,7 @@ These are the global settings for the BlobStorage API.
 
 ``` yaml
 openapi-type: data-plane
-tag: package-2021-12
+tag: package-2024-08
 use-internal-constructors: true
 add-credentials: true
 ```
@@ -93,6 +93,15 @@ input-file:
 - stable/2021-12-02/blob.json
 ```
 
+### Tag: package-2024-08
+
+These settings apply only when `--tag=package-2024-08` is specified on the command line.
+
+``` yaml $(tag) == 'package-2024-08'
+input-file:
+- stable/2024-08-04/blob.json
+```
+
 ### Suppression
 ``` yaml
 directive: