Add tagging information to stackset schema (#124)

cr: https://code.amazon.com/reviews/CR-166548407

Co-authored-by: Samyak Kumar <ksamyak@amazon.com>

Author: oshardik

aws-cloudformation-stackset/aws-cloudformation-stackset.json

@@ -371,6 +371,13 @@
       "/properties/StackSetName"
     ]
   ],
+  "tagging": {
+    "taggable": true,
+    "tagOnCreate": true,
+    "tagUpdatable": true,
+    "cloudFormationSystemTags": false,
+    "tagProperty": "/properties/Tags"
+  },
   "handlers": {
     "create": {
       "permissions": [