tests: use nodes and threads variables

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
tests: add latency_probe launcher for Vesta

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
tests: use nodes and threads in job template for latency_probe on Mira

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
tests: simplify latency_probe script for Cetus

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
thorium: use the old congestion detection since it produced higher utilization

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
thorium: reduce congestion threshold to 1

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
scripts: add -print-thorium-data to latency_probe test

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>