update and fix i18n spec

Failing after upgrading vue-loader in https://github.com/bahmutov/cypress-vue-unit-test/pull/331

Spec translated-message-spec.js

<img width="1144" alt="Screen Shot 2020-07-01 at 11 49 22 AM" src="https://user-images.githubusercontent.com/2212006/86264886-10849d80-bb91-11ea-8c68-521d2f01436e.png">
