New shadow sim runner from chi-node-0N machine
We could make use of a new shadow runner, set up similar to ci-runner-x86-03-shadow, to be able to run multiple simulations at once. We have about 50 sims to run for congestion control, and we may need to run a similar number for conflux.
Right now, simulations are requiring 200GB of RAM and ~20-40 cores. I expect the RAM requirements to increase, though, once we have a look at utilization as compared to baseline (we may need to increase the # of tor clients).
So ideally we'd be able to dedicate the entirety of one of the chi-node-0[1-4] machines to this task. In a pinch, we could even use node 8-10 and 12-13, as we have run sims in 192GB recently, but again I suspect that might not be sufficient in the long run.
Cc: @jnewsome to comment on other requirements.