tests: add request_bogus_size

This attempts to reproduce the error conditions from
https://gitlab.freedesktop.org/wayland/wayland/issues/52

 and make it crash.
While the crash was repeatable in my tests, it depends on garbage on stack
leading to access of invalid memory, which is not guaranteed.

This is a FAIL_TEST, so that the following fix commit can be verified.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Simon Ser <contact@emersion.fr>