test: use regular timeout times for ARMv8

ARMv8 machines are typically quite fast and likely may not need
extended timeout times.

PR-URL: https://github.com/nodejs/node/pull/4248


Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>