[release] 4.2.1

package.json

 {
   "name": "vue-element-admin",
-  "version": "4.2.0",
+  "version": "4.2.1",
   "description": "A magical vue admin. An out-of-box UI solution for enterprise applications. Newest development stack of vue. Lots of awesome features",
   "author": "Pan <panfree23@gmail.com>",
   "license": "MIT",