add breaking change warning for upcoming addition for confirmation during account redundancy change

Author: calvinhzy

src/azure-cli/azure/cli/command_modules/storage/_breaking_change.py

@@ -0,0 +1,18 @@
+# --------------------------------------------------------------------------------------------
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License. See License.txt in the project root for license information.
+# --------------------------------------------------------------------------------------------
+
+from azure.cli.core.breaking_change import register_other_breaking_change
+
+register_other_breaking_change('storage account migration start',
+                               message='Starting from 5/19, changing redundancy configuration would require additional '
+                                       '(y/n) confirmation: "After your request to convert the account’s redundancy '
+                                       'configuration is validated, the conversion will typically complete in a few '
+                                       'days, but can take several weeks depending on current resource demands in the '
+                                       'region, account size, and other factors. The conversion can’t be stopped after '
+                                       'being initiated, and for accounts with geo redundancy a failover can’t be '
+                                       'initiated while conversion is in progress. The data within the storage account '
+                                       'will continue to be accessible with no loss of durability or availability. '
+                                       'Confirm redundancy configuration change: (y/n)"',
+                               target_version='2.73.0')