tests: newlib/thread_safety: exclude acrn_ehl_crb from more tests

This was already excluded from
libraries.libc.newlib_nano.thread_safety.userspace.stress and it's now
failing in libraries.libc.newlib.thread_safety.userspace.stress as well.

The issue is being rootcaused to a toolchain issue but a proper fix has
not been identified yet, exclude that test as well in the meantime.

Link: https://github.com/zephyrproject-rtos/zephyr/issues/61129


Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>