bug 402301: Migration: UI Independent tests

Add tests in:
* org.eclipse.scout.rt.testing.client.test
* org.eclipse.scout.rt.testing.server.test

https://bugs.eclipse.org/bugs/show_bug.cgi?id=402301

Change-Id: Iacee6ef9bb76a11d6ea34f777628a3fd9c5eeea0