Restore DBFTPlugin Unit Tests (ConsensusService and Consensus Context)

[vncoelho]

Tries to close https://github.com/neo-project/neo/issues/3231

[vncoelho]

Get some examples for mock from https://github.com/neo-project/neo-modules/pull/836

[cschuchardt88]

[vncoelho]

I see it is on Dev branch, maybe it is better to merge as it is and we create other PRs. This PR is already too old

[vncoelho]

In fact, SimulateCompleteConsensusRoundAsync was not a test method,

[Jim8y]

@Jim8y

I tried to modify some tests to produce errors

Like this, the WaitForConsensusMessages should fail because I did not send PrepareRequest.

I think that we still need some minor modifications before merging to "dev". Maybe we could also remove some duplicated tests and code. I am missing coveralls to analyse that more carefully (ping @shargon )

But, overall, the design looks great.

I need to access ConsensusContext of the Actors in order to verify some states after messages are sent and service starts. I am still not sure how to do that.

Sure vitor, give me one day to refactoring this pr to match your review expection.

[shargon]

Only 25% is covered, but it's a good start

[Wi1l-B0t]

Test time too long

Neo.Plugins.DBFTPlugin.Tests test succeeded (34.0s)