Bump mockito-core from 2.20.1 to 2.21.0
Bump mockito-core from 2.20.1 to 2.21.0

Bumps [mockito-core](https://github.com/mockito/mockito) from 2.20.1 to 2.21.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](https://github.com/mockito/mockito/compare/v2.20.1...v2.21.0)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
zalando/riptide,zalando/riptide,whiskeysierra/riptide,whiskeysierra/riptide