gitlab: wrap up test results for custom runners

gitlab: wrap up test results for custom runners

Instead of spewing the whole log to stdout lets just define them as
build artefacts so we can examine them later. Where we are running
check-tcg run it first as those tests are yet to be integrated into
meson. To avoid confusion we don't run multiple check-tcg tests at
once.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-18-alex.bennee@linaro.org>