Doesn't build with gradle 4

[mihxil]

I actually never use gradle, but in any case, my naive try to build this project didn't work:

mihxil@baleno:~/github/mihxil/spring-mvc-cache-control$ ./gradlew 

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/mihxil/github/mihxil/spring-mvc-cache-control/build.gradle' line: 78

* What went wrong:
A problem occurred configuring project ':spring-mvc-cache-control'.
> cannot get property 'repoUser' on extra properties extension as it does not exist

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Total time: 3.631 secs