test: fix flaky test-domain-abort-on-uncaught

test-domain-abort-on-uncaught is flaky under load. Move it to sequential
so it is not competing with other tests for resources.

PR-URL: #11817
Fixes: #11814
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Daijiro Wachi <daijiro.wachi@gmail.com>
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>
Reviewed-By: Yuta Hiroto <hello@about-hiroppy.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: Trott