Interop: make action-tests interact with contracts

[protolambda]

The system interop tests currently have bindings to 3 contracts:

• an emitter contract, to emit log events
• the L1 system config, to emit dependency-set changes
• a crossL2Inbox contract interface, to execute messages

These bindings can be found here: https://github.com/ethereum-optimism/optimism/tree/develop/op-e2e/interop/contracts
We should move this whole package into a new op-e2e/e2eutils/interop package, so the bindings are available to the action tests.

In the op-e2e/actions/interop we can then instantiate the bindings per L2 chain.
And use them to run through executing messages between chains, similar to the system test, but in the action-test format, for a more controlled environment for debugging.