Test container plugin dependencies should be added automatically

[kapexx]

For junit-plugin configurations, the documentation of container says "If the container points to a plugin project, the plugin will be added to the dependency list as well". This partly works, the plugin is added to the dependencies. But that plugin's transitive dependencies are not added automatically. It seems like the container plugin is not part of the automatic dependency resolution.

Example: Assuming we have two plugin projects, org.example.demo.test which depends on org.example.demo. In the following configuration org.example.demo.test is added as dependency because the container points to that plugin project. Launching it will fail because org.example.demo is missing though.

junit-plugin configuration Demo {
    test {
        runner junit5;
        container '/org.example.demo.test';
    }
    application org.eclipse.pde.junit.runtime.coretestapplication;
    plugin slf4j.simple;
}

Only if we add the container plugin redundantly in the dependencies, then org.example.demo is added automatically as expected.

junit-plugin configuration Demo {
    test {
        runner junit5;
        container '/org.example.demo.test';
    }
    application org.eclipse.pde.junit.runtime.coretestapplication;
    plugin slf4j.simple;
    plugin org.example.demo.test;
}