Simulator network configuration and stress test

[mystenmark]

Support for configuring the network using the simulator's SimConfig struct. (See MystenLabs/mysten-sim#3 for background).

Adds a new test which runs the stress tester inside the simulator. This test can currently expose various bugs/errors when run with a higher latency network. The default target that is checked in uses low latency and thus will pass in CI.

@sadhansood is there an easy way to get a failure signal from the BenchDriver, e.g. a callback every time a transaction fails? Right now I don't have a good way to make this test fail if errors are encountered.

[sadhansood]

@mystenmark the BenchmarkStats object that is returned by the BenchDriver has num_errors and num_success metric in it. We could pass in the run_duration as some finite value (5 mins, 1 hour, etc) and check the resulting stats for %error_rate and fail the test if it's too high.

[mystenmark]

@mystenmark the BenchmarkStats object that is returned by the BenchDriver has num_errors and num_success metric in it. We could pass in the run_duration as some finite value (5 mins, 1 hour, etc) and check the resulting stats for %error_rate and fail the test if it's too high.

I took a look at that, but apparently the errors that I'm seeing aren't resulting in client facing errors, so they don't show up in the BenchmarkStats - I'll need to find some other way to instrument those.

I added a simple assert for 0 errors for now.

We can add longer tests, but I'll need to set up a nightly job for longer tests - I don't want to add very long running tests to CI.