Spring boot i18N problem

Hi all~
How do I internationalize the Camunda webapps when using spring-boot?
I found this example
camunda-7-code-examples

I have copied zh-CN.json file to src/main/resources/webjars/camunda/app/tasklist/locales folder, and configured config.js like this…

...
  'locales': {
    'availableLocales': ['zh-CN', 'en'],
    'fallbackLocale': 'en'
  },
...

The language of my browser is zh-CN and I already cleaned the chache, but it doesn’t work… What should I do?

regards
Hao