docs: slot-scope deprecated (#1072)

Author: Jet12138

docs/zh-cn/features/es2015.md

@@ -48,7 +48,7 @@ export default {
 
 ``` html
 <my-component>
-  <template scope="{ id, text }">
+  <template slot-scope="{ id, text }">
     <span>{{ id }} {{ text }}</span>
   </template>
 </my-component>