fix leak (#890)

Former-commit-id: c7aa52e

Author: paul-nechifor

dimos/utils/testing/replay.py

@@ -389,7 +389,7 @@ def emit() -> None:
                         if hasattr(scheduler, "dispose"):
                             scheduler.dispose()
 
-                disp.add(scheduler.schedule_relative(delay, lambda sc, _: emit()))
+                scheduler.schedule_relative(delay, lambda sc, _: emit())
 
             schedule_emission(next_message)