Native testing breaks test cacheability

[melix]

If native testing is enabled (and it's enabled by default), then tests caching is broken. More specifically, tests executed from a different directory are not cached.

The Gradle build cache should be able to reuse test results, for example, if the project is checked out in a different directory. However, a system property is added which uses an absolute path:

native-build-tools/native-gradle-plugin/src/main/java/org/graalvm/buildtools/gradle/NativeImagePlugin.java

Line 366 in 00a8cc3

test.systemProperty(JUNIT_PLATFORM_LISTENERS_UID_TRACKING_OUTPUT_DIR, testListDirectory.getAsFile().get());

This causes cache misses in case the project is used in a different directory.