错误:A problem occurred configuring project ':app'.
Could not download junit.jar (junit:junit:4.12)
Could not get resource 'https://jcenter.bintray.com/junit/junit/4.12/junit-4.12.jar'.
> Could not GET 'https://jcenter.bintray.com/junit/junit/4.12/junit-4.12.jar'.
> d29vzk4ow07wi7.cloudfront.net