The extracted tests rely on access to system devices
or global state that prevent them from being run in parallel
or in restricted environments.
As an integration test they will be executed separately and
single threaded.
Updates the test runner to ensure integration tests are actually
run single threaded as intended.
BUG=b:244623061
TEST=./tools/run_tests base:\* --repeat 100 -p x86_64/mingw64/aarch64
Change-Id: I4267b9f79055208aca86796d902da251816bcada
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3971025
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Dennis Kempin <denniskempin@google.com>
