Link caniuse feature for @scope (#1190)

Author: foolip

features/scope.yml

@@ -1,6 +1,7 @@
 name: "@scope"
 description: The `@scope` CSS at-rule sets the scope for a group of rules.
 spec: https://drafts.csswg.org/css-cascade-6/#scope-atrule
+caniuse: css-cascade-scope
 usage_stats: https://chromestatus.com/metrics/feature/timeline/popularity/4212
 compat_features:
   - api.CSSScopeRule