Currently the concurrency suites are failing some MR workloads due to OOM errors. The tests are being run on default using resmoke_jobs: 4. Instead, we should reduce this to a smaller number like 1. We can consider using the resmoke_jobs_factor option (eg. https://github.com/mongodb/mongo/blob/c6845bd41a393eedd3e1e979fef030d277de7144/etc/evergreen.yml#L10089).