I have just migrated to JDK 11 in order to use the latest Java LTS version. If I change the execution JRE in Eclipse from 10 to 11 (and only then), when I try to run my test
Was the same problem. Add Mockito 2.22.0 to dependencies. Everything seems to work.
compile group: 'org.mockito', name: 'mockito-core', version: '2.22.0'