Exceptions from Simulator do not properly end Tests

[mkorbel1]

Describe the bug

If Simulator.run throws an exception, the Test should immediately end (and fail). However, as currently implemented in start, it can cause a hang instead.

Depends on fix from intel/rohd#515

Once the ROHD fix is available, it should be possible to wait for Simulator.simulationEnded and separately start it with unawaited(Simulator.run()), which should allow the exception to throw all the way up instead of hanging quietly.

To Reproduce

Throw an exception in a registerEndOfSimulationAction, then start the test.

Expected behavior

Test fails

Actual behavior

Test hangs

Additional: Dart SDK info

No response

Additional: pubspec.yaml

No response

Additional: Context

No response