Expanding tests run in coverage job #1676

I changed the configuration for https://ci.nodejs.org/view/All/job/node-test-commit-linux-coverage-daily/ to also run pummel and benchmark jobs.

Under "Execute Shell", I changed the last line from this:

NODE_TEST_DIR=${HOME}/node-tmp PYTHON=python COVTESTS="test-ci test-internet" make coverage -j $(getconf _NPROCESSORS_ONLN)

...to this:

NODE_TEST_DIR=${HOME}/node-tmp PYTHON=python COVTESTS="test-ci test-internet test-pummel test-benchmark" make coverage -j $(getconf _NPROCESSORS_ONLN)

Once nodejs/node#25799 lands, we can replace the list of suites with test-all-suites and all tests under the test directory will run no matter where they are.