Dynamic values for earliestBlockNumber and latestBlockNumber for EndStream in simulator publisher

[mustafauzunn]

Story Form

As a developer
I want to be able to use publisher simulator
So that I can send EndStream without the need for manual setting of earliestBlockNumber and latestBlockNumber

Technical Notes

Currently, earliestBlockNumber and latestBlockNumber are set manually from BlockStreamConfig. It will be easier and more reliable if these values are set dynamically by the simulator.