test: Fix flaky test_emit_system_info_event by waiting on event

tests/unit/events/test_local_event_manager.py

@@ -11,15 +11,19 @@
 
 async def test_emit_system_info_event() -> None:
     mocked_listener = AsyncMock()
+    received = asyncio.Event()
 
     async def async_listener(payload: Any) -> None:
         await mocked_listener(payload)
+        received.set()
 
     system_info_interval = timedelta(milliseconds=50)
-    test_tolerance_coefficient = 10
     async with LocalEventManager(system_info_interval=system_info_interval) as event_manager:
         event_manager.on(event=Event.SYSTEM_INFO, listener=async_listener)
-        await asyncio.sleep(system_info_interval.total_seconds() * test_tolerance_coefficient)
+        # Wait until the listener is invoked at least once. A generous timeout avoids flakiness on
+        # loaded CI runners, where `psutil.cpu_percent(interval=0.1)` in `asyncio.to_thread` can
+        # delay the first emission well beyond the configured interval.
+        await asyncio.wait_for(received.wait(), timeout=10)
 
     assert mocked_listener.call_count >= 1
     assert isinstance(mocked_listener.call_args[0][0], EventSystemInfoData)