remove extra "required" prop (#1249)
remove extra "required" prop (#1249)

Remove `required` prop because it has been minxined at `mixins: [Base]` base.js file Line: 6
airyland/vux,greedying/vux,huixt/hxvux,greedying/vux,greedying/vux,huixt/hxvux,airyland/vux,huixt/hxvux,airyland/vux