error in HelloDominion demo

[smurfer]

When I run the HelloDominion example given in demo_ecs, the program does not terminate. The below error message is repeated indefinitely until the process is terminated:

Entity null moved with Velocity[x=1.0, y=1.0] to Position{x=31.0, y=31.0}
the end
SEVE         dominion.SystemScheduler invoke 
java.lang.IllegalStateException: java.lang.IllegalStateException: Dominion 'dominion-1' has already been closed.

(using VS Code, Maven, JDK 23)