[test] Use JUnit 5

[at15]

• idea support it https://blog.jetbrains.com/idea/2016/08/using-junit-5-in-intellij-idea/
• I don't have much experience w/ JUnit 4 as well, just run and assert, no much lost for migration
• http://junit.org/junit5/docs/current/user-guide/

[at15]

it seems JUnit 5 can't generate report using gradle command https://github.com/junit-team/junit5-samples/tree/master/junit5-gradle-consumer

The results of any tests run via the JUnit Platform Gradle plugin will not be included in the standard test report generated by Gradle; however, the test results can typically be aggregated by your CI server software. See the reportsDir property of the plugin

[at15]

and it mentioned container? not docker container .... I'm thinking too much

Two conditional extension points exist, ContainerExecutionCondition and TestExecutionCondition, and they can be used to deactivate either all tests in a container (likely a class) or individual tests (likely a test method).

from https://blog.codefx.org/libraries/junit-5-conditions/

[at15]

I think I am still using it like JUnit4 ..... most advance features are not used, but anyway, it's running