In JDK-8169285, we enabled SWT tests. Those may fail on some Linux distros. They are therefore disabled on Linux as of now.

We discovered various problems:
1. GDK_BACKEND=x11 need to be set in the args. This is normally set in launcher.c, but might be too late for SWT. We track this in JDK-8340378
2. It may work on Ubuntu 24.04.2, but did not for all of us.