feat(ui): babel feature description

Author: Guillaume Chau

packages/@vue/cli/lib/promptModules/babel.js

@@ -3,6 +3,7 @@ module.exports = cli => {
     name: 'Babel',
     value: 'babel',
     short: 'Babel',
+    description: 'Transpile modern JavaScript to older versions (for compatibility)',
     checked: true
   })