Added license

Author: rsinghal26

src/neon/azext_neon/_breaking_change.py

@@ -1,3 +1,7 @@
+# --------------------------------------------------------------------------------------------
+# 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_command_group_deprecate
 from azure.cli.core.breaking_change import register_other_breaking_change