Need Test for SmallestMailbox Router

[VaughnVernon]

The test must create a subclass of SmallestMailboxRouter, which can be seen here:

https://github.com/vlingo/vlingo-actors/blob/master/src/main/java/io/vlingo/actors/SmallestMailboxRouter.java

The test must also create two or more other actors that implement a protocol to serve as workers. It is the worker actors whose mailbox sizes need to be controlled by the test cases to verify that the SmallestMailboxRouter in fact selects the routee with the fewest pending messages.

Note that the following exposes the routee’s pending message count to the router.

https://github.com/vlingo/vlingo-actors/blob/0e18f6dd41fce33ed7b97a7a08fd14e76de84c34/src/main/java/io/vlingo/actors/Routee.java#L50

There is already a test case stub https://github.com/vlingo/vlingo-actors/blob/master/src/test/java/io/vlingo/actors/SmallestMailboxRouterTest.java

You may also benefit by reviewing/using the vlingo-telemetry component.