Update tests for new empire support
The task is to update tests to match new plan description and communication from https://gitlab.ics.muni.cz/beast-public/cryton-fork/cryton-worker/-/issues/8, https://gitlab.ics.muni.cz/beast-public/cryton-fork/cryton-worker/-/issues/7, https://gitlab.ics.muni.cz/beast-public/cryton-fork/cryton-core/-/issues/19, and https://gitlab.ics.muni.cz/beast-public/cryton-fork/cryton-core/-/issues/20.