Bump mockito-core from 2.28.2 to 3.0.0

Bumps [mockito-core](https://github.com/mockito/mockito) from 2.28.2 to 3.0.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](mockito/mockito@v2.28.2...v3.0.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

build.gradle

@@ -62,7 +62,7 @@ dependencies {
     compile group: 'com.squareup.okhttp', name: 'okhttp', version: '2.7.5'
     compile files('libs/go-plugin-util.jar')
     compile group: 'javax.xml.bind', name: 'jaxb-api', version: '2.3.1'
-    testCompile group: 'org.mockito', name: 'mockito-core', version: '2.28.2'
+    testCompile group: 'org.mockito', name: 'mockito-core', version: '3.0.0'
     testCompile group: 'junit', name: 'junit', version: '4.12'
     testCompile group: 'org.hamcrest', name: 'hamcrest-library', version: '2.1'
 }