Extract Warp Test into Simulator Workload

[aaronbuchwald]

This ticket is to extract the logic for the warp load test running in CI https://github.com/ava-labs/subnet-evm/blob/master/tests/warp/warp_test.go#L100 into the simulator tool https://github.com/ava-labs/subnet-evm/tree/master/cmd/simulator, so that it can be easily run against an existing DevNet.

[marun]

Will this work with #1027 ?

[aaronbuchwald]

The idea here was to build this into a utility that could be run from the command line, so ideally this would integrate really nicely if we get the interface for the network fixture right.

Ideally the current simulator and the warp extension of it could take in a network definition to construct the fixture to run against and then execute the workload against that.

If we worked on them simultaneously, I'd imagine they'd conflict, but I'd hope they are both moving in the same direction.