Resolve a build issue.

Author: EmmaZhu

src/Common/Storage/Commands.Storage.Test/Service/MockStorageBlobManagement.cs

@@ -680,6 +680,16 @@ public Task<BlobResultSegment> ListBlobsSegmentedAsync(CloudBlobContainer contai
             throw new NotImplementedException();
         }
 
+        /// <summary>
+        /// Get the SAS token for an account.
+        /// </summary>
+        /// <param name="sharedAccessAccountPolicy">Shared access policy to generate the SAS token.</param>
+        /// <returns>Account SAS token.</returns>
+        public string GetStorageAccountSASToken(SharedAccessAccountPolicy sharedAccessAccountPolicy)
+        {
+            throw new NotImplementedException();
+        }
+
         /// <summary>
         /// The storage context
         /// </summary>